Methods for treating lignocellulosic materials

ABSTRACT

The present invention relates to methods of processing lignocellulosic material to obtain hemicellulose sugars, cellulose sugars, lignin, cellulose and other high-value products. Also provided are hemicellulose sugars, cellulose sugars, lignin, cellulose, and other high-value products.

CROSS-REFERENCE

This application claims the benefit under 35 USC §119(e) of U.S.Provisional Application No. 61/642,338, filed on May 3, 2012, U.S.Provisional Application No. 61/662,830, filed on Jun. 21, 2012, U.S.Provisional Application No. 61/693,637, filed on Aug. 27, 2012, U.S.Provisional Application No. 61/672,719, filed on Jul. 17, 2012, U.S.Provisional Application No. 61/720,313, filed on Oct. 30, 2012, U.S.Provisional Application No. 61/680,183, filed on Aug. 6, 2012, U.S.Provisional Application No. 61/680,661, filed on Aug. 7, 2012, U.S.Provisional Application No. 61/720,325, filed on Oct. 30, 2012, U.S.Provisional Application No. 61/785,891, filed on Mar. 14, 2013, U.S.Provisional Application No. 61/680,181, filed on Aug. 6, 2012, U.S.Provisional Application No. 61/681,299, filed on Aug. 9, 2012, U.S.Provisional Application No. 61/715,703, filed on Oct. 18, 2012, and U.S.Provisional Application No. 61/786,169, filed on Mar. 14, 2013, eachincorporated herein by reference in its entirety.

STATEMENT AS TO FEDERALLY SPONSORED RESEARCH

This invention was made with government support under Grant No.DE-EE0005003 awarded by the Department of Energy. The government hascertain rights in the invention.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

FIELD OF THE INVENTION

The invention relates to processing of lignocellulosic biomass materialscontaining lignin, cellulose and hemicellulose polymers.

BACKGROUND OF THE INVENTION

Lignocellulosic biomass materials are renewable sources for productionof amino acids for feed and food supplements, monomers and polymers forthe plastic industry, and renewable sources for different types offuels, polyol sugar substitutes (xylitol, sorbitol, manitols and thelikes), and numerous other chemicals that can be synthesized from C5 andC6 sugars. Nonetheless, efficient and cost effective processes toextract C5 and C6 sugars from the biomass are still a challenge.Lignocellulosic biomass materials are composite materials that containsnot only the lignocellulosic polymers, but also a wide variety of smallamounts of lipophilic or amphiphilic compounds, e.g., fatty acids, rosinacids, phytosteroids, as well as proteins and ash element. Whenhydrolyzing the hemicellulose polymers, ester bonds on the sugarmolecules can also be hydrolyzed, releasing the un-substituted sugarmolecule along with a significant amount of methanol and acetic acid.Additional organic acids such as lactic acid, glucoronic acid,galacturonic acid, formic acid and levullinic acid are also typicallyfound in cellulosic hydrolysate. In addition to these, the ligninpolymer tends to release under mild hydrolyzing conditions some smallchain aqueous soluble lignin molecules. Consequently, the typicalhydrolysate is a very complex solution of multiple components. Thisposes a significant challenge in separation and refining of the sugarsto obtain useful grades of the extracted sugars.

SUMMARY OF THE INVENTION

The invention provides methods of refining a sugar stream. The methodinvolves (i) contacting the sugar stream with an amine extractant toform a mixture; and (ii) separating from the mixture a first streamcomprising the amine extractant and an acid or an impurity; and a secondstream comprising one or more sugars. Optionally, the first stream is anorganic stream and the second stream is an aqueous stream. Optionally,the first stream comprises less than 0.5% w/w sugars. Optionally, thesecond stream comprises less than 0.5% w/w acid. Optionally, the secondstream comprises less than 0.5% w/w amine. Optionally, the second streamcomprises less than 0.5% w/w impurities. Optionally, impurities areextracted from the sugar stream into the amine extractant. In someembodiments, the method further involves, prior to step (i), contactingthe sugar stream with a strong acid cation exchanger to remove residualcations. Optionally, the amine extractant comprises an amine and adiluent. Optionally, the ratio of the amine and the diluent is 3:7.Optionally, the ratio of the amine and the diluent is 5.5:4.55.Optionally, the ratio of the amine and the diluent is between 3:7 and6:4. Optionally, the diluent comprises an alcohol. Optionally, thediluent comprises a C6, C8, C10, C12, C14, C16 alcohol or kerosene.Optionally, the diluent comprises hexanol. Optionally, the amine is anamine comprising at least 20 carbon atoms. Optionally, the amine istri-laurylamine. In some embodiments, the method further involvesremoving diluent from the second stream using a packed distillationcolumn. Optionally, at least 95% of diluent in the second stream isremoved. In some embodiments, the method further involves contacting thesugar stream with a strong acid cation exchanger to remove residualamines, thereby forming an amine-removed hydrolysate. In someembodiments, the method further involves contacting the amine-removedhydrolysate with a weak base anion exchanger to form a neutralizedhydrolysate. In some embodiments, the method further involvesevaporating the hydrolysate to form a concentrated hydrolysate. In someembodiments, the method further involves fractionating the hydrolysateinto a monomeric sugar stream and an oligomeric sugar stream. In someembodiments, the method further involves purifying or concentrating themonomeric sugar stream. In some embodiments, the method furtherinvolves, prior to contacting the sugar stream with an amine extractantto form a first mixture, allowing residual acid in the sugar streamhydrolyze at least some oligomeric sugars in the sugar stream intomonomeric sugars. Optionally, the method further involves, prior toallowing, diluting the sugar stream to a lower sugar concentration.Optionally, the method further involves, prior to allowing, increasingthe acid concentration in the sugar stream. Optionally, the acidconcentration is increased to be more than 0.5%. In some embodiments,the method further involves combining the oligomeric sugar stream withthe sugar stream before the sugar stream is contacted with the amineextract; wherein the residual acid in the sugar stream hydrolyzes atleast some oligomeric sugars in the oligomeric sugar stream intomonomeric sugars. Optionally, the method further involves contacting thefirst stream with a base solution to form a neutralized amineextractant. Optionally, the contacting is conducted at 70° C.Optionally, the method further involves prior to contacting the firststream with a base solution, further comprising washing the first streamwith an aqueous stream to remove sugar from the first stream.Optionally, the washed first stream comprises less than 0.1%weight/weight sugar. Optionally, the method further involves washing atleast a portion of the neutralized amine extractant with water, andrecycling the washed amine extractant. Optionally, the method furtherinvolves treating part of the washed neutralized amine extractant streamby heating it with 10% lime. Optionally, the contacting is conducted at80-90° C.

The invention further provides methods for removing acid from an acidichemicellulose sugars stream. The method involves (i) contacting anacidic hemicellulose sugar stream comprising an acid and one or morehemicellulose sugars with an amine extractant to form an amine mixture;and (ii) separating from the amine mixture a first stream comprising theacid and the amine extractant, and a second stream comprising thehemicellulose sugar stream. In some embodiments, the method furtherinvolves prior to step (i), contacting a lignocellulosic feedstock withan acidic aqueous solution; and separating the acidic aqueous solutionfrom the lignocellulosic feedstock thereby forming a lignocellulosicstream and the acidic hemicellulose sugar stream. Optionally, the firststream is an organic stream and the second stream is an aqueous stream.Optionally, the first stream comprises less than 0.5% w/w hemicellulosesugars. Optionally, the second stream comprises less than 0.5% w/w acid.Optionally, the second stream comprises less than 0.5% w/w amine.Optionally, the second stream comprises less than 0.5% w/w impurities.Optionally, impurities are extracted from the acidic hemicellulose sugarstream into the amine extractant. Optionally, the amine extractantcomprises an amine and a diluent. Optionally, the ratio of the amine andthe diluent is 3:7. Optionally, the ratio of the amine and the diluentis 5.5:4.55. Optionally, the ratio of the amine and the diluent isbetween 3:7 and 6:4. Optionally, the diluent comprises an alcohol.Optionally, the diluent comprises a C6, C8, C10, C12, C14, C16 alcoholor kerosene. Optionally, the diluent comprises hexanol. Optionally, theamine is an amine comprising at least 20 carbon atoms. Optionally, theamine is tri-laurylamine. Optionally, the acidic aqueous solutioncomprises 0.1-2% acid. Optionally, the acid comprises H2SO4 and/or SO2and/or H2SO3, and/or HCl. In some embodiments, the method furtherinvolves removing diluent from the second stream using a packeddistillation column. Optionally, at least 95% of diluent in the secondstream is removed. In some embodiments, the method further involvescontacting the second stream with a strong acid cation exchanger toremove residual amines thereby forming an amine-removed sugar stream. Insome embodiments, the method further involves contacting theamine-removed sugar stream with a weak base anion exchanger to form aneutralized sugar stream. In some embodiments, the method furtherinvolves evaporating the sugar stream thereby forming a concentratedsugar solution. In some embodiments, the method further involvesfractionating the sugar stream into a xylose-enriched stream and a mixedsugar stream. Optionally, the sugars are fractionated using anion-exchange resin. Optionally, the ion-exchange column is an anionexchange resin. Optionally, the anion exchange resin has a particle sizein the range of 200-400 μm. Optionally, the anion exchange resin has aparticle size in the range of 280-320 μm. Optionally, the fractionationis carried out in a simulated moving bed mode. Optionally, thefractionation is carried out in a sequential simulated moving bed mode.Optionally, the sequential simulated moving bed chromatography systemcomprises steps 1-3; a feed stream in passed into an adsorbent and afirst raffinate stream is flushed from the adsorbent during step 1; asecond raffinate stream is flushed from the adsorbent with a desorbentstream during step 2; and the desorbent is recycled back to theadsorbent during step 3; wherein the xylose-enriched stream is extractedin both step 1 and step 2. Optionally, the desorbent flow rate of thechromatography system is equal to the sum of the extract flow rate andthe raffinate flow rate. In some embodiments, the method furtherinvolves crystallizing xylose from the xylose-enriched stream. In someembodiments, the method further involves contacting the first streamwith a base solution to form a neutralized extractant. In someembodiments, the method further involves, prior to contacting the firststream with a base solution, further comprising washing the first streamwith an aqueous stream to remove hemicellulose sugar from the firststream. Optionally, the washed first stream comprises less than 0.1%weight/weight sugar. In some embodiments, the method further involveswashing the neutralized extractant with water, and recycling the washedamine extractant. In some embodiments, the method further involvestreating part of the washed neutralized extractant by heating it with10% lime. Optionally, the lignocellulosic stream is used to makebioenergy pellets.

The invention further provides methods for fractionating a liquid samplecomprising a mixture of a first fraction and a second fraction. Themethod involves (i) fractionating the liquid sample with a sequentialsimulated moving bed chromatography system; wherein the sequentialsimulated moving bed chromatography system comprises steps 1-3; a feedstream in passed into an adsorbent and a first raffinate stream isflushed from the adsorbent during step 1; a second raffinate stream isflushed from the adsorbent with a desorbent stream during step 2; andthe desorbent is recycled back to the adsorbent during step 3; (ii)recovering one or more product stream from the chromatography system;wherein the product stream is extracted in both step 1 and step 2.Optionally, the liquid sample further comprises a third fraction.Optionally, desorbent flow rate of the chromatography system is equal tothe sum of the extract flow rate and the raffinate flow rate.Optionally, the chromatography system comprises an ion-exchange resin.Optionally, the ion-exchange resin is an anion exchange resin.Optionally, the ion-exchange resin has a particle size in the range of200-400 μm. Optionally, the ion-exchange resin has a particle size inthe range of 280-320 μm.

The invention further provides a hemicellulose sugar mixture. Themixture comprises one or more, two or more, three or more, four or more,five or more, or six or seven or eight or more of the followingcharacteristics: (i) monosaccharides in a ratio to total dissolvedsugars >0.50 weight/weight; (ii) glucose in a ratio to totalmonosaccharides <0.25 weight/weight; (iii) xylose in a ratio to totalmonosaccharides >0.18 weight/weight; (iv) fructose in a ratio to totalmonosaccharides <0.10 weight/weight; (v) fructose in a ratio to totalmonosaccharides >0.01 weight/weight; (vi) furfurals in an amount up to0.01% weight/weight; and (vii) one or more phenols in an amount up to500 ppm; and (viii) hexanol in an amount up to 0.1% weight/weight.Optionally, the monosaccharides to total dry solid ratio is >0.70weight/weight. Optionally, the monosaccharides to total dry solid ratiois >0.90 weight/weight. Optionally, the glucose to total monosaccharidesratio is <0.15 weight/weight. Optionally, the glucose to totalmonosaccharides ratio is <0.13 weight/weight. Optionally, the glucose tototal monosaccharides ratio is <0.06 weight/weight. Optionally, thexylose to total monosaccharides ratio is >0.20 weight/weight.Optionally, the xylose to total monosaccharides ratio is >0.50weight/weight. Optionally, the xylose to total monosaccharides ratiois >0.70 weight/weight. Optionally, the fructose to totalmonosaccharides ratio is >0.02 weight/weight. Optionally, the fructoseto total monosaccharides ratio is <0.08 weight/weight. Optionally, themixture contains furfurals in an amount up to 0.005% weight/weight.Optionally, the mixture contains furfurals in an amount up to 0.001%weight/weight. Optionally, the mixture contains phenols in an amount upto 400 ppm. Optionally, the mixture contains phenols in an amount up to300 ppm.

The invention further provides a xylose-enriched stream hemicellulosesugar mixture. The mixture comprises one or more, two or more, three ormore, four or more, five or more, six or more, seven or more, eight ormore, nine or more, or ten or more of the following characteristics: (i)oligosaccharides in a ratio to total dissolved sugars <0.10weight/weight; (ii) xylose in a ratio to total dissolved sugars >0.50weight/weight; (iii) arabinose in a ratio to total dissolved sugars<0.10 weight/weight; (iv) galactose in a ratio to total dissolved sugars<0.05 weight/weight; (v) the sum of glucose and fructose in a ratio tototal dissolved sugars <0.10 weight/weight; (vi) mannose in a ratio tototal dissolved sugars <0.02 weight/weight; (vii) fructose in a ratio tototal dissolved sugars <0.05 weight/weight; (viii) furfurals in anamount up to 0.01% weight/weight; (ix) phenols in an amount up to 500ppm; and (x) hexanol in an amount up to 0.1% weight/weight. Optionally,the oligosaccharides to total dissolved sugars ratio is <0.07.Optionally, the oligosaccharides to total dissolved sugars ratio is<0.05. Optionally, the xylose to total dissolved sugars ratio is >0.40weight/weight. Optionally, the xylose to total dissolved sugars ratiois >0.70 weight/weight. Optionally, the xylose to total dissolved sugarsratio is >0.80 weight/weight. Optionally, the sum of glucose andfructose to total dissolved sugars ratio is <0.09. Optionally, the sumof glucose and fructose to total dissolved sugars ratio is <0.05.Optionally, the mixture contains furfurals in an amount up to 0.005%weight/weight. Optionally, the mixture contains furfurals in an amountup to 0.001% weight/weight. Optionally, the mixture contains phenols inan amount up to 60 ppm. Optionally, the mixture contains phenols in anamount up to 0.05 ppm.

The invention further provides a xylose-removed hemicellulose sugarmixture. The mixture comprises one or more, two or more, three or more,four or more, five or more, six or more, seven or more, eight or more,nine or more, or ten or more of the following characteristics: (i)oligosaccharides in a ratio to total dissolved sugars >0.15weight/weight; (ii) the sum of glucose and fructose in a ratio to totaldissolved sugars >0.20 weight/weight; (iii) arabinose in a ratio tototal dissolved sugars >0.02 weight/weight; (iv) galactose in a ratio tototal dissolved sugars >0.02 weight/weight; (v) xylose in a ratio tototal dissolved sugars <0.20; (vi) mannose in a ratio to total dissolvedsugars >0.01; (vii) fructose in a ratio to total dissolved sugars <0.05;(viii) furfurals in an amount up to 0.01% weight/weight; (ix) phenols inan amount up to 500 ppm; and (x) hexanol in an amount up to 0.1%weight/weight. Optionally, the oligosaccharides to total dissolvedsugars ratio is >0.20 weight/weight. Optionally, the oligosaccharides tototal dissolved sugars ratio is >0.23 weight/weight. Optionally, theoligosaccharides to total dissolved sugars ratio is >0.25 weight/weight.Optionally, the sum of glucose and fructose to total dissolved sugarsratio is >0.10 weight/weight. Optionally, the sum of glucose andfructose to total dissolved sugars ratio is >0.25 weight/weight.Optionally, the sum of glucose and fructose to total dissolved sugarsratio is >0.35 weight/weight. Optionally, the mixture contains furfuralsin an amount up to 0.005% weight/weight. Optionally, the mixturecontains furfurals in an amount up to 0.001% weight/weight. Optionally,the mixture contains phenols in an amount up to 60 ppm. Optionally, themixture contains phenols in an amount up to 0.05 ppm. Optionally, thexylose to total dissolved sugars ratio is <0.30 weight/weight.Optionally, the xylose to total dissolved sugars ratio is <0.15weight/weight. Optionally, the xylose to total dissolved sugars ratio is<0.10 weight/weight.

The invention further provides a mother liquor hemicellulose sugarmixture. The mixture comprises one or more, two or more, three or more,four or more, five or more, six or more, seven or more, eight or more,nine or more, or ten or more of the following characteristics: (i)oligosaccharides in a ratio to total dissolved sugars <0.15weight/weight; (ii) xylose in a ratio to total dissolved sugars >0.40weight/weight; (iii) arabinose in a ratio to total dissolved sugars<0.15 weight/weight; (iv) galactose in a ratio to total dissolved sugars<0.06 weight/weight; (v) the sum of glucose and fructose in a ratio tototal dissolved sugars <0.20 weight/weight; (vi) mannose in a ratio tototal dissolved sugars <0.03; (vii) fructose in a ratio to totaldissolved sugars <0.04; (viii) furfurals in an amount up to 0.01%weight/weight; (ix) phenols in an amount up to 500 ppm; and (x) hexanolin an amount up to 0.1% weight/weight. Optionally, the oligosaccharidesto total dissolved sugars ratio is <0.12. Optionally, theoligosaccharides to total dissolved sugars ratio is <0.10. Optionally,the oligosaccharides to total dissolved sugars ratio is <0.20.Optionally, the xylose to total dissolved sugars ratio is >0.50weight/weight. Optionally, the xylose to total dissolved sugars ratiois >0.60 weight/weight. Optionally, the xylose to total dissolved sugarsratio is >0.70 weight/weight. Optionally, the sum of glucose andfructose to total dissolved sugars ratio is <0.30. Optionally, the sumof glucose and fructose to total dissolved sugars ratio is <0.20.Optionally, the sum of glucose and fructose to total dissolved sugarsratio is <0.10. Optionally, the mixture contains furfurals in an amountup to 0.005% weight/weight. Optionally, the mixture contains furfuralsin an amount up to 0.001% weight/weight. Optionally, the mixturecontains phenols in an amount up to 60 ppm. Optionally, the mixturecontains phenols in an amount up to 0.05 ppm.

The invention further provides a method of producing a cellulose sugarstream. The method involves (i) moving a lignocellulosic stream and anacid stream counter-currently through a plurality of stirred tankreactors to produce an acidic hydrolysate stream and an acidic ligninstream; and (ii) separating the acidic hydrolysate stream from theacidic lignin stream; wherein the plurality of stirred tank reactorsincludes a first reactor, a last reactor, and one or more intermediatereactors; wherein the lignocellulosic stream enters the first reactor,the acid stream enters the last reactor, the acidic hydrolysate streamexits from the first reactor, and the lignin stream exits from the lastreactor. In some embodiments, the method further involves, prior to step(i), contacting a lignocellulosic feedstock with an acidic aqueoussolution; and separating the acidic aqueous solution from thelignocellulosic feedstock thereby forming an acidic hemicellulose sugarstream and the lignocellulosic stream. In some embodiments, the methodfurther involves, prior to step (i), reducing particle size in thelignocellulosic stream to 400 to 5000 microns. Optionally, the acidichydrolysate stream comprises one or more cellulose sugars. Optionally,the acidic hydrolysate stream further comprises one or morehemicellulose sugars. In some embodiments, the method further involves(iii) contacting the acidic hydrolysate stream comprising an acid andone or more cellulose sugars with a S1 solvent extractant to form afirst mixture; and (iv) separating from the first mixture a first streamcomprising the acid and the S1 solvent extractant and a second streamcomprising the one or more cellulose sugars; wherein the acid isextracted from the acidic hydrolysate stream into the S1 solventextractant. Optionally, the contacting is conducted at 50° C. In someembodiments, the method further involves (v) evaporating the secondstream comprising the one or more cellulose sugars to form aconcentrated second stream; and (vi) repeating step (iii) and (iv) aboveto form a stream comprising the acid and the S1 solvent extractant and astream comprising the one or more cellulose sugars. Optionally, theacidic hydrolysate stream is evaporated before the acidic hydrolysatestream is contacted with the S1 solvent extractant, thereby reducing theacid concentration in the acidic hydrolysate stream to azeotrope.Optionally, the first stream is an organic stream and the second streamis an aqueous stream. In some embodiments, the method further involves(v) contacting the second stream with an amine extractant to form asecond mixture; and (vi) separating from the second mixture a thirdstream comprising the acid and the amine extractant and a fourth streamcomprising the one or more cellulose sugars. In some embodiments, themethod further involves, prior to contacting the second stream with anamine extractant to form a second mixture, allowing the residual acid inthe second stream hydrolyze at least some oligomeric sugars in the sugarstream into monomeric sugars thereby forming a cellulose sugar stream.In some embodiments, the method further involves, prior to allowing,diluting the second stream to a lower sugar concentration. Optionally,an oligomeric sugar stream is added to the second stream before thesecond stream is contacted with the amine extract; wherein the residualacid in the second stream hydrolyzes at least some oligomeric sugars inthe mixture of the oligomeric sugar stream and the second stream intomonomeric sugars. Optionally, the third stream is an organic stream andthe fourth stream is an aqueous stream. Optionally, the acidichydrolysate stream is separated from the lignin stream using a filter,membrane, or hydroclone. Optionally, the acid stream comprise at least40% weight/weight acid. Optionally, the S1 solvent extractant comprisesan alcohol. Optionally, the S1 solvent extractant comprises a C6, C8,C10, C12, C14, C16 alcohol or kerosene or a mixture thereof. Optionally,the S1 solvent extractant comprises hexanol. Optionally, the amineextractant comprises an amine and a diluent. Optionally, the ratio ofthe amine and the diluent is 3:7. Optionally, the ratio of the amine andthe diluent is 5.5:4.55. Optionally, the ratio of the amine and thediluent is between 3:7 and 6:4. Optionally, the diluent comprises analcohol. Optionally, the diluent comprises a C6, C8, C10, C12, C14, C16alcohol or kerosene. Optionally, the diluent comprises hexanol.Optionally, the amine is an amine comprising at least 20 carbon atoms.Optionally, the amine is tri-laurylamine. Optionally, thelignocellulosic feedstock comprises mainly cellulose and lignin.Optionally, at least a portion of the acidic hydrolysate stream leavingone or more intermediate tank is added to the lignocellulosic streambefore the lignocellulosic stream enters the first reactor. Optionally,the lignocellulosic stream is heated. Optionally, the acid hydrolysatestream contains 22-33% acid weight/weight. In some embodiments, themethod further involves removing diluent from the fourth stream using apacked distillation column. Optionally, at least 95% of diluent in thefourth stream is removed. In some embodiments, the method furtherinvolves contacting the fourth stream with a strong acid cationexchanger to remove residual amines, thereby forming an amine-removedhydrolysate. In some embodiments, the method further involves contactingthe amine-removed hydrolysate with a weak base anion exchanger to form aneutralized hydrolysate. In some embodiments, the method furtherinvolves evaporating the hydrolysate to form a concentrated hydrolysate.In some embodiments, the method further involves fractionating thehydrolysate into a monomeric sugar stream and an oligomeric sugarstream. In some embodiments, the method further involves purifying orconcentrating the monomeric sugar stream. In some embodiments, themethod further involves combining the oligomeric sugar stream with thesecond stream before the second stream is contacted with the amineextract; wherein the residual acid in the second stream hydrolyzes atleast some oligomeric sugars in the oligomeric sugar stream intomonomeric sugars. In some embodiments, the method further involvescontacting the first stream comprising the acid and the S1 solventextractant with an aqueous solution to form a deacidified extractant andan aqueous back-extract; wherein the acid is extracted from the firststream into the aqueous back-extract. Optionally, the contacting isconducted at 50° C. In some embodiments, the method further involves,prior to contacting the first stream with an aqueous solution to form adeacidified extractant and an aqueous back-extract, contacting the firststream with an azeotropic or higher concentration acid solution torecover sugars from the first stream. Optionally, the aqueousback-extract comprising 15-20% acid and is used in a downstream process.In some embodiments, the method further involves evaporating the aqueousback-extract under a first pressure, thereby generates asuper-azeotropic acid solution having an acid concentration higher thanthat of the aqueous back-extract prior to the evaporation. In someembodiments, the method further involves evaporating thesuper-azeotropic acid solution under a second pressure to generate asuper-azeotropic gaseous acid, wherein the second pressure is higherthan the first pressure. In some embodiments, the method furtherinvolves absorbing the super-azeotropic gaseous acid in an aqueoussolution to produce a concentrated acid solution. In some embodiments,the method further involves contacting the third stream with a basesolution to form a neutralized amine extractant. Optionally, thecontacting is conducted at 70° C. In some embodiments, the methodfurther involves, prior to contacting the third stream with a basesolution, further comprising washing the third stream with an aqueousstream to remove cellulose sugar from the third stream. Optionally, thewashed third stream comprises less than 0.1% weight/weight cellulosesugar. In some embodiments, the method further involves washing at leasta portion of the neutralized amine extractant with water, and recyclingthe washed amine extractant. In some embodiments, the method furtherinvolves treating part of the washed neutralized amine extractant streamby heating it with 10% lime. Optionally, the contacting is conducted at80-90° C.

The invention further provides a method of hydrolyzing oligomericsugars. The method involves (i) contacting an acidic hydrolysate streamcomprising an acid and one or more cellulose sugars with a S1 solventextractant to form a first mixture; (ii) separating from the firstmixture a first stream comprising the acid and the S1 solvent extractantand a second stream comprising the one or more cellulose sugars; whereinthe acid is extracted from the acidic hydrolysate stream into the S1solvent extractant; (iii) allowing the residual acid in the secondstream hydrolyze at least some oligomeric sugars in the sugar streaminto monomeric sugars thereby forming a cellulose sugar stream; and (iv)fractionating the cellulose sugar stream into a monomeric sugar streamand an oligomeric sugar stream. In some embodiments, the method furtherinvolves, prior to fractionating, adding an oligomeric sugar stream intothe second stream, wherein the residual acid in the second streamhydrolyzes at least some oligomeric sugars in the mixture of the secondstream and the oligomeric sugar stream into monomeric sugars therebyforming a cellulose sugar stream. In some embodiments, the methodfurther involves, prior to allowing, diluting the second stream to alower sugar concentration. In some embodiments, the method furtherinvolves, prior to allowing, increasing the acid concentration in thesecond stream. Optionally, the acid concentration is increased to bemore than 0.5%. Optionally, the acidic hydrolysate stream is evaporatedbefore the input stream is contacted with the S1 solvent extractant,thereby reducing the acid concentration in the acidic hydrolysate streamto azeotrope. In some embodiments, the method further involvescontacting the cellulose sugar stream with an anion exchanger to removeacid from the stream. Optionally, the hydrolyzing is catalyzed by HCl ata concentration of not more than 1.2% weight/weight. Optionally, thehydrolyzing is catalyzed by HCl at a concentration of not more than 0.7%weight/weight. Optionally, the hydrolyzing is performed at a temperaturein the range between 60° C. and 150° C. Optionally, the secondaryhydrolysate contains at least 70% monomeric sugars out of total sugarsweight/weight. Optionally, the total sugar content of said secondaryhydrolysate is at least 90% weight/weight of the sugar content of saidaqueous, low acid mixture.

The invention further provides a high concentration C6 sugar mixture.The mixture comprises one or more, two or more, three or more, or fouror more, five or more, or six or more of the following characteristics:(i) monosaccharides in a ratio to total dissolved sugars >0.85weight/weight; (ii) glucose in a ratio to total dissolved sugars in therange of 0.40-0.70 weight/weight; (iii) 1-200 ppm chloride; (iv)furfurals in an amount up to 0.01% weight/weight; (v) phenols in anamount up to 500 ppm; and (vi) hexanol in an amount up to 0.1%weight/weight. Optionally, the monosaccharides to total dissolved sugarsratio is >0.90 weight/weight. Optionally, the monosaccharides to totaldissolved sugars ratio is >0.95 weight/weight. Optionally, the glucoseto total dissolved sugars ratio is in the range of 0.40-0.60weight/weight. Optionally, the glucose to total dissolved sugars ratiois in the range of 0.50-0.60 weight/weight. Optionally, the chlorideconcentration is in the range of 10-100 ppm. Optionally, the chlorideconcentration is in the range of 10-50 ppm. Optionally, the mixturecontains furfurals in an amount up to 0.005% weight/weight. Optionally,the mixture contains furfurals in an amount up to 0.001% weight/weight.Optionally, the mixture contains phenols in an amount up to 400 ppm.Optionally, the mixture contains phenols in an amount up to 100 ppm.Optionally, xylose to total dissolved sugars ratio is in the range of0.03-0.12 weight/weight. Optionally, xylose to total dissolved sugarsratio is in the range of 0.05-0.10 weight/weight. Optionally, arabinoseto total dissolved sugars ratio is in the range of 0.005-0.015weight/weight. Optionally, galactose to total dissolved sugars ratio isin the range of 0.025-0.035 weight/weight. Optionally, mannose to totaldissolved sugars ratio is in the range of 0.14-0.18 weight/weight.

The invention further provides a method of producing a high puritylignin. The method involves (i) adjusting the pH of an aqueous solutioncomprising lignin to an acidic pH; (ii) contacting the acidic aqueouslignin solution with a lignin extraction solution comprising alimited-solubility solvent thereby forming a first stream comprising thelignin and the lignin extraction solution, and a second streamcomprising water soluble impurities; (iii) contacting the first streamwith a strong acid cation exchanger to remove residual cations therebyobtaining a purified first stream; and (iv) separating thelimited-solubility solvent from the lignin thereby obtaining a highpurity lignin composition. Optionally, the separating step comprisesprecipitating the lignin by contacting the purified first stream withwater. Optionally, the purified first stream is contacted with hot waterthereby flash evaporating the limited-solubility solvent. Optionally,the separating step comprises evaporating the limited-solubility solventfrom the lignin. Optionally, the evaporating comprises spray drying. Insome embodiments, the method further involves filtering the ligninparticles from the water. Optionally, the aqueous solution comprisinglignin is generated by dissolving a lignin material in an alkalinesolution. Optionally, the aqueous solution comprising lignin isgenerated by a process selected from a pulping, a milling, abiorefining, kraft pulping, sulfite pulping, caustic pulping,hydro-mechanical pulping, mild acid hydrolysis of lignocellulosefeedstock, concentrated acid hydrolysis of lignocellulose feedstock,supercritical water or sub-supercritical water hydrolysis oflignocellulose feedstock, ammonia extraction of lignocellulosefeedstock. Optionally, the lignin material is a deacidified lignin; themethod further comprising, prior to step (i), contacting an acidiclignin with a hydrocarbon solvent to form a mixture; heating thehydrocarbon solvent to remove acid from the mixture thereby obtaining adeacidified lignin. Optionally, the pH of the aqueous lignin solution isadjusted to 3.5-4. Optionally, the first stream is an organic stream andthe second stream is an aqueous stream. Optionally, the lignin materialis an acidic lignin obtained by extracting hemicellulose sugar from alignocellulosic feedstock followed by cellulose hydrolysis using anacid. Optionally, the lignin material is a deacidified lignin.Optionally, the aqueous solution is water. Optionally, the aqueoussolution is an acidulant.

The invention further provides a method of producing a deacidifiedlignin. The method involves contacting an acidic lignin with ahydrocarbon solvent; and heating the hydrocarbon solvent to remove anacid from the acidic lignin thereby obtaining a deacidified lignin.Optionally, the acidic lignin is obtained by removing hemicellulose andcellulose material from a lignocellulosic feedstock. Optionally, thehydrocarbon is ISOPARK. Optionally, the limited-solubility solvent ismethylethylketone. Optionally, the acidic lignin is washed with anaqueous wash solution to remove residual sugars and acid before theacidic lignin is contacted with the hydrocarbon solvent. Optionally, theaqueous wash solution is an aqueous back-extract according to certainembodiments of the present invention. Optionally, the lignin material iswashed with the aqueous solution counter-currently. Optionally, thelignin material is washed in multiple stages. Optionally, the highpurity lignin is characterized by at least one, two, three, four, five,six, seven, eight, nine, ten, eleven, twelve or thirteen characteristicselected from the group consisting of: (i) lignin aliphatic hydroxylgroup in an amount up to 2 mmole/g; (ii) at least 2.5 mmole/g ligninphenolic hydroxyl group; (iii) at least 0.4 mmole/g lignin carboxylichydroxyl group; (iv) sulfur in an amount up to 1% weight/weight; (v)nitrogen in an amount up to 0.05% weight/weight; (vi) chloride in anamount up to 0.1% weight/weight; (vii) 5% degradation temperature higherthan 250° C.; (viii) 10% degradation temperature higher than 300° C.;(ix) low ash content; (x) a formula of CaHbOc; wherein a is 9, b is lessthan 10 and c is less than 3; (xi) a degree of condensation of at least0.9; (xii) a methoxyl content of less than 1.0; and (xiii) an O/C weightratio of less than 0.4.

The invention further provides a lignin composition characterized by atleast one, two, three, four, five, six, seven, eight, nine, ten, eleven,twelve or thirteen characteristic selected from the group consisting of:(i) lignin aliphatic hydroxyl group in an amount up to 2 mmole/g; (ii)at least 2.5 mmole/g lignin phenolic hydroxyl group; (iii) at least 0.4mmole/g lignin carboxylic hydroxyl group; (iv) sulfur in an amount up to1% weight/weight; (v) nitrogen in an amount up to 0.05% weight/weight;(vi) chloride in an amount up to 0.1% weight/weight; (vii) 5%degradation temperature higher than 250° C.; (viii) 10% degradationtemperature higher than 300° C.; (ix) low ash content; (x) a formula ofCaHbOc; wherein a is 9, b is less than 10 and c is less than 3; (xi) adegree of condensation of at least 0.9; (xii) a methoxyl content of lessthan 1.0; and (xiii) an O/C weight ratio of less than 0.4. Optionally,the lignin composition comprises lignin aliphatic hydroxyl group in anamount up to 1 mmole/g. Optionally, the lignin composition compriseslignin aliphatic hydroxyl group in an amount up to 0.5 mmole/g.Optionally, the lignin composition comprises at least 2.7 mmole/g ligninphenolic hydroxyl group. Optionally, the lignin composition comprises atleast 3.0 mmole/g lignin phenolic hydroxyl group. Optionally, the lignincomposition comprises at least 0.4 mmole/g lignin carboxylic hydroxylgroup. Optionally, the lignin composition comprises at least 0.9 mmole/glignin carboxylic hydroxyl group.

The invention further provides a lignin composition characterized by atleast one, two, three, or four characteristic selected from the groupconsisting of: (i) at least 97% lignin on a dry matter basis; (ii) anash content in an amount up to 0.1% weight/weight; (iii) a totalcarbohydrate content in an amount up to 0.05% weight/weight; and (iv) avolatiles content in an amount up to 5% weight/weight at 200° C.Optionally, the mixture has a non-melting particulate content in anamount up to 0.05% weight/weight.

The invention further provides a method of producing high purity ligninfrom a biomass. The method involves (i) removing hemicellulose sugarsfrom the biomass thereby obtaining a lignin-containing remainder;wherein the lignin-containing remainder comprises lignin and cellulose;(ii) contacting the lignin-containing remainder with a lignin extractionsolution to produce a lignin extract and a cellulosic remainder; whereinthe lignin extraction solution comprises a limited-solubility solvent,an organic acid, and water, wherein the limited-solubility solvent andwater form an organic phase and an aqueous phase; and (iii) separatingthe lignin extract from the cellulosic remainder; wherein the ligninextract comprises lignin dissolved in the limited-solubility solvent.Optionally, the removal of the hemicellulose sugars does not remove asubstantial amount of the cellulosic sugars. Optionally, thelimited-solubility solvent and the water in the lignin extractionsolution is in a ratio of about 1:1. In some embodiments, the methodfurther involves purifying the cellulosic remainder to obtain cellulosepulp. Optionally, the cellulose pulp comprises lignin in an amount up to10% weight/weight. Optionally, the cellulose pulp comprises lignin in anamount up to 7% weight/weight. In some embodiments, the method furtherinvolves contacting the lignin extract with a strong acid cationexchanger to remove residual cations thereby obtaining a purified ligninextract. In some embodiments, the method further involves separating thelimited-solubility solvent from the lignin extract thereby obtaininghigh purity lignin. In some embodiments, the method further involvesevaporating the limited-solubility solvent from the lignin. Optionally,the evaporating comprises spray drying. In some embodiments, the methodfurther involves washing the cellulose remainder with thelimited-solubility solvent and with water thereby obtaining cellulosepulp. In some embodiments, the method further involves contacting thecellulose pulp with an acid to produce an acidic hydrolysate streamcomprising cellulose sugars. In some embodiments, the method furtherinvolves (i) contacting the acidic hydrolysate stream comprising an acidand one or more cellulose sugars with a S1 solvent extractant to form afirst mixture; and (ii) separating from the first mixture a first streamcomprising the acid and the S1 solvent extractant and a second streamcomprising the one or more cellulose sugars; wherein the acid isextracted from the acidic hydrolysate stream into the S1 solventextractant. In some embodiments, the method further involves (iii)evaporating the second stream comprising the one or more cellulosesugars to form a concentrated second stream; and (vi) repeating step(iii) and (iv) above to form a stream comprising the acid and the S1solvent extractant and a stream comprising the one or more cellulosesugars. In some embodiments, the method further involves (v) contactingthe second stream with an amine extractant to form a second mixture; and(vi) separating from the second mixture a third stream comprising theacid and the amine extractant and a fourth stream comprising the one ormore cellulose sugars. In some embodiments, the method further involveshydrolyzing the cellulose pulp in an aqueous suspension comprisinghydrolytic enzymes. In some embodiments, the method further involves (i)agitating or stirring of the suspension comprising the cellulose pulp,the hydrolytic enzymes and an acidulating agent in a temperaturecontrolled tank; (ii) separating from the suspension a first streamcomprising cellulose pulp and a second stream comprising hydrolyzedcellulose sugars; (iii) returning the first stream to the temperaturecontrolled tank for further hydrolysis. Optionally, the separating iscarried out using a separation device selected from a filter, amembrane, a centrifuge, a hydrocylone. Optionally, the concentration ofdissolved glucose in the aqueous suspension is controlled below theinhibition level of the hydrolytic enzymes. In some embodiments, themethod further involves (i) contacting the second stream with an amineextractant to form a first mixture; and (ii) separating from the firstmixture a third stream comprising the acid and the amine extractant anda fourth stream comprising the one or more cellulose sugars. In someembodiments, the method further involves allowing the residual acid inthe fourth stream hydrolyze at least some oligomeric sugars in the sugarstream into monomeric sugars thereby forming a cellulose sugar stream.In some embodiments, the method further involves, prior to allowing,diluting the second stream to a lower sugar concentration. In someembodiments, the method further involves, prior to allowing, increasingthe acid concentration in the second stream. Optionally, the acidconcentration is increased to be more than 0.5%. In some embodiments,the method further involves contacting the fourth stream with a strongacid cation exchanger to remove residual amines, thereby forming anamine-removed hydrolysate. In some embodiments, the method furtherinvolves contacting the amine-removed hydrolysate with a weak base anionexchanger to form a neutralized hydrolysate. In some embodiments, themethod further involves evaporating the hydrolysate to form aconcentrated hydrolysate. In some embodiments, the method furtherinvolves fractionating the hydrolysate into a monomeric sugar stream andan oligomeric sugar stream. In some embodiments, the method furtherinvolves purifying or concentrating the monomeric sugar stream. In someembodiments, the method further involves (iv) contacting the firststream with an alkaline solution thereby dissolving residual solidlignin in the cellulose pulp; (v) separating the remainder cellulosepulp from the dissolved lignin thereby forming an aqueous solutioncomprising lignin; (vi) adjusting the pH of an aqueous solutioncomprising lignin to an acidic pH; (vii) contacting the acidic aqueouslignin solution with a lignin extraction solution comprising alimited-solubility solvent thereby forming a third stream comprising thelignin and the lignin extraction solution, and a fourth streamcomprising water soluble impurities; (viii) contacting the third streamwith a strong acid cation exchanger to remove residual cations therebyobtaining a purified third stream; and (ix) separating thelimited-solubility solvent from the lignin thereby obtaining a highpurity lignin composition. Optionally, the separating is carried out byfiltering. Optionally, the separating step comprises precipitating thelignin by contacting the purified first stream with water. Optionally,the purified third stream is contacted with hot water thereby flashevaporating the limited-solubility solvent. Optionally, the separatingstep comprises evaporating the limited-solubility solvent from thelignin. Optionally, the evaporating comprises spray drying.

The invention further provides a method for producing a conversionproduct. The method involves (i) providing a fermentor; and (ii)fermenting a medium comprising at least one member selected from thegroup consisting of a hemicellulose sugar mixture according to certainembodiments of the invention; a xylose-enriched stream hemicellulosesugar mixture according to certain embodiments of the invention; axylose stream according to certain embodiments of the invention (e.g., acrystallized xylose stream or a re-dissolved xylose stream); axylose-removed hemicellulose sugar mixture according to certainembodiments of the invention; a mother liquor hemicellulose sugarmixture according to certain embodiments of the invention; a highconcentration C6 sugar mixture according to certain embodiments of thepresent invention, in the fermentor to produce a conversion product. Theinvention further provides a method for producing a conversion product(i) providing at least one member selected from the group consisting ofa hemicellulose sugar mixture according to certain embodiments of theinvention; a xylose-enriched stream hemicellulose sugar mixtureaccording to certain embodiments of the invention; a xylose streamaccording to certain embodiments of the invention (e.g., a crystallizedxylose stream or a re-dissolved xylose stream); a xylose-removedhemicellulose sugar mixture according to certain embodiments of theinvention; a mother liquor hemicellulose sugar mixture according tocertain embodiments of the invention; a high concentration C6 sugarmixture according to certain embodiments of the invention; and (ii)converting sugars in the at least one member to a conversion productusing a chemical process. In some embodiments, the methods furtherinvolve processing the conversion product to produce a consumer productselected from the group consisting of detergent, polyethylene-basedproducts, polypropylene-based products, polyolefin-based products,polylactic acid (polylactide)-based products, polyhydroxyalkanoate-basedproducts and polyacrylic-based products. Optionally, the conversionproduct includes at least one member selected from the group consistingof alcohols, carboxylic acids, amino acids, monomers for the polymerindustry and proteins. Optionally, the detergent comprises a sugar-basedsurfactant, a fatty acid-based surfactant, a fatty alcohol-basedsurfactant, or a cell-culture derived enzyme. Optionally, thepolyacrylic-based products are selected the group consisting ofplastics, floor polishes, carpets, paints, coatings, adhesives,dispersions, flocculants, elastomers, acrylic glass, absorbent articles,incontinence pads, sanitary napkins, feminine hygiene products anddiapers. Optionally, the polyole fin-based products are selected fromthe group consisting of milk jugs, detergent bottles, margarine tubs,garbage containers, water pipes, absorbent articles, diapers,non-wovens, HDPE toys and HDPE detergent packagings. Optionally, thepolypropylene-based products are selected from the group consisting ofabsorbent articles, diapers, and non-wovens. Optionally, the polylacticacid-based products are selected from the group consisting of packagingof agriculture products and of dairy products, plastic bottles,biodegradable products and disposables. Optionally, thepolyhydroxyalkanoate-based products are selected from the groupconsisting of packaging of agriculture products, plastic bottles, coatedpapers, molded or extruded articles, feminine hygiene products, tamponapplicators, absorbent articles, disposable non-wovens, wipes, medicalsurgical garments, adhesives, elastomers, films, coatings, aqueousdispersants, fibers, intermediates of pharmaceuticals and binders.Optionally, the conversion product includes at least one member selectedfrom the group consisting of ethanol, butanol, isobutanol, a fatty acid,a fatty acid ester, a fatty alcohol and biodiesel. In some embodiments,the methods further involve processing of the conversion product toproduce at least one product selected from the group consisting of anisobutene condensation product, jet fuel, gasoline, gasohol, dieselfuel, drop-in fuel, diesel fuel additive and a precursor thereof.Optionally, the gasohol is ethanol-enriched gasoline or butanol-enrichedgasoline. Optionally, the product is selected from the group consistingof diesel fuel, gasoline, jet fuel and drop-in fuels.

The invention further provides a consumer product, a precursor of aconsumer product, or an ingredient of a consumer product produced from aconversion product according to methods for producing a conversionproduct described herein. The invention further provides a consumerproduct, a precursor of a consumer product, or an ingredient of aconsumer product comprising at least one conversion product produced bymethods for producing a conversion product described herein, wherein theconversion product is selected from the group consisting of carboxylicand fatty acids, dicarboxylic acids, hydroxylcarboxylic acids, hydroxyldi-carboxylic acids, hydroxyl-fatty acids, methylglyoxal, mono-, di-, orpoly-alcohols, alkanes, alkenes, aromatics, aldehydes, ketones, esters,biopolymers, proteins, peptides, amino acids, vitamins, antibiotics andpharmaceuticals. Optionally, the product is ethanol-enriched gasoline,jet fuel, or biodiesel. Optionally, the consumer product has a ratio ofcarbon-14 to carbon-12 of about 2.0×10⁻¹³ or greater. Optionally, theconsumer product comprising an ingredient according to certainembodiments of the present invention and an additional ingredientproduced from a raw material other than lignocellulosic material.Optionally, the ingredient and the additional ingredient produced from araw material other than lignocellulosic material are essentially of thesame chemical composition. Optionally, the consumer product, theprecursor of a consumer product, or the ingredient of a consumer productfurther comprises a marker molecule at a concentration of at least 100ppb. Optionally, the marker molecule is selected from the groupconsisting of furfural, hydroxymethylfurfural, products of furfural orhydroxymethylfurfural condensation, color compounds derived from sugarcaramelization, levulinic acid, acetic acid, methanol, galacturonic acidand glycerol.

The invention further provides a method of converting lignin into aconversion product. The method involves (i) providing a compositionaccording to certain embodiments of the present invention, and (ii)converting at least a portion of lignin in the composition to aconversion product. Optionally, the converting comprises treating withhydrogen. In some embodiments, the method further involves producinghydrogen from lignin. Optionally, the conversion product comprises atleast one item selected from the group consisting of bio-oil, carboxylicand fatty acids, dicarboxylic acids, hydroxyl-carboxylic, hydroxyldi-carboxylic acids and hydroxyl-fatty acids, methylglyoxal, mono-, di-or poly-alcohols, alkanes, alkenes, aromatics, aldehydes, ketones,esters, phenols, toluenes, and xylenes. Optionally, the conversionproduct comprises a fuel or a fuel ingredient. Optionally, theconversion product comprises para-xylene. Optionally, a consumer productproduced from the conversion product or a consumer product containingthe conversion product as an ingredient or component. Optionally, theproduct contains at least one chemical selected from the groupconsisting of lignosulfonates, bio-oil, carboxylic and fatty acids,dicarboxylic acids, hydroxyl-carboxylic, hydroxyl di-carboxylic acidsand hydroxyl-fatty acids, methylglyoxal, mono-, di- or poly-alcohols,alkanes, alkenes, aromatics, aldehydes, ketones, esters, biopolymers,proteins, peptides, amino acids, vitamins, antibiotics, paraxylene andpharmaceuticals. Optionally, the product contains para-xylene.Optionally, the product is selected from the group consisting ofdispersants, emulsifiers, complexants, flocculants, agglomerants,pelletizing additives, resins, carbon fibers, active carbon,antioxidants, flame retardant, liquid fuel, aromatic chemicals,vanillin, adhesives, binders, absorbents, toxin binders, foams,coatings, films, rubbers and elastomers, sequestrants, fuels, andexpanders. Optionally, the product is used in an area selected from thegroup consisting of food, feed, materials, agriculture, transportationand construction. Optionally, the product has a ratio of carbon-14 tocarbon-12 of about 2.0×10⁻¹³ or greater. Optionally, the productcontains an ingredient according to certain embodiments of the presentinvention and an ingredient produced from a raw material other thanlignocellulosic material. Optionally, the ingredient according tocertain embodiments of the present invention and the ingredient producedfrom a raw material other than lignocellulosic material are essentiallyof the same chemical composition. Optionally, the product contains amarker molecule at a concentration of at least 100 ppb. Optionally, themarker molecule is selected from the group consisting of furfural andhydroxy-methyl furfural, products of their condensation, colorcompounds, acetic acid, methanol, galcturonic acid, glycerol, fattyacids and resin acids.

DESCRIPTION OF THE FIGURES

FIGS. 1-6 are simplified flow schemes of methods for treatinglignocellulose material according to some embodiments of the invention.

FIG. 7 depicts a chromatographic fractionation of a refined sugar mix toobtain an enriched xylose fraction and a mix sugar solution containingglucose, arabinose and a variety of DP2+ components.

FIG. 8A is a simplified scheme of a counter current stirred reactorsystem for hydrolysis of cellulose in an aqueous solution containingHCl. FIG. 8B summarizes results collected during a eucalyptus hydrolysiscampaign utilizing the system described in FIG. 8A including 4 stirredtanks over 30 days of continuous operation. The black lines denotetarget values of acid and dissolved sugar; the gray lines denote acidand sugar levels of each stage (tank).

FIG. 9 A depicts the level of acid in the aqueous phase stream comingoff the hydrolysis system (gray lines), the level after solventextraction A (black lines) and the level after solvent extraction B(light gray lines). FIG. 9B depicts the level of sugars in the solventfollowing acid extraction into the solvent (gray lines) and the level ofsugars in the solvent after scrubbing the sugars into an acid solution(black lines). FIG. 9C depicts the level of acid in the loaded solventstream (light gray lines), the level of acid in the solvent after backextraction (black lines) and the resulting level in the aqueous phase(gray lines).

FIG. 10 Depicts the % mono sugars/total sugars in the aqueous solutionafter solvent extraction (gray lines) and after second hydrolysis (blacklines). DP1 stands for monosaccharide.

FIG. 11 A: the level of residual hydrochloric acid in the aqueous streamafter second hydrolysis. B: percent removal of acidity from the aqueousphase into the amine solvent phase.

FIG. 12 Impurities analysis of the S1 solvent after purification byliming. Only accumulation of hexyl acetate is noticed while all othermajor impurities are maintained at a very low level, indicating that thepurification process should be slightly stronger to remove acetate moreeffectively.

FIG. 13 depicts production of super azeotropic HCl solution of >41%obtained by directing a flow of HCl gas that is distilled from theaqueous solutions to a lower concentration HCl solution

FIG. 14A is a simplified scheme of a system for lignin washing FIG. 14Bdepicts the average concentration of acid and sugar in the lignin washsystem per stage: black lines—acid concentration; gray line—sugarconcentration. Sugar concentration is reduced from more than 30% to lessthan 3%, while acid concentration is reduced from more than 33% to lessthan 5%.

FIG. 15 (A) ³¹P NMR spectrum of high purity lignin; (B)¹³C NMR spectrumof lignin.

FIG. 16 is a simplified flow diagram of an exemplary of cellulosic sugarfractionation according to some embodiments of the present invention.

FIG. 17 is a schematic representation of an exemplary method of treatinglignocellulosic biomass material according to some embodiments of thepresent invention.

FIG. 18 is a schematic representation of an exemplary method ofhemicellulose sugar extraction and purification according to someembodiments of the present invention. GAC stands for granulatedactivated carbon. MB stands for mixed bed (e.g., mixed bed cation/anionresin).

FIG. 19 is a schematic representation of an exemplary method ofcellulose hydrolysis and main sugar refining according to someembodiments of the present invention.

FIG. 20 is a schematic representation of an exemplary method of ligninprocessing according to some embodiments of the present invention.

FIG. 21 is a schematic representation of an exemplary method of ligninrefining according to some embodiments of the present invention.

FIG. 22 depicts an exemplary method of hydrolysis of cellulose bycellulase according to some embodiments of the present invention.

FIG. 23 is a simplified flow scheme according to some alternativelignocellulosic biomass processing and acid recovery embodiments of theinvention.

FIG. 24 is a simplified flow scheme according to some alternativelignocellulosic biomass processing and acid recovery embodiments of theinvention.

FIG. 25 is a schematic overview of an exemplary hydrolysis system whichproduces a lignin stream that serves as an input stream in variousexemplary embodiments of the invention.

FIG. 26 a is a schematic overview of a de-acidification system in accordwith some exemplary cellulose sugar refining embodiments of theinvention.

FIG. 26 b is a schematic overview of an optional solvent and/or waterremoval system according to some exemplary cellulose sugar refiningembodiments of the invention.

FIG. 26 c is a schematic overview of an optional pre-evaporation moduleaccording to some exemplary cellulose sugar refining embodiments of theinvention.

FIG. 26 d is a schematic overview of a de-acidification system similarto that of FIG. 26 a depicting optional additional or alternativecomponents.

FIG. 27 is a simplified flow diagram of a method according toalternative cellulose sugar refining embodiments of the invention.

FIG. 28 is a simplified flow diagram of a method according toalternative cellulose sugar refining embodiments of the invention.

FIG. 29 is a simplified flow diagram of a method according toalternative cellulose sugar refining embodiments of the invention.

FIG. 30 is a schematic representation of a system similar to that inFIG. 26 b indicating flow control components.

FIG. 31 a is a simplified flow diagram of a method according toalternative embodiments of monosaccharides fermentation and chemicalconversions.

FIG. 31 b is a simplified flow diagram of a method according toalternative embodiments of monosaccharides fermentation and chemicalconversions.

FIG. 32 is a simplified flow diagram of a method according toalternative cellulose sugar refining embodiments of the invention.

FIG. 33 is a simplified flow diagram of a method according toalternative cellulose sugar refining embodiments of the invention.

FIG. 34 is a simplified flow diagram of a method according toalternative lignin processing embodiments of the invention.

FIG. 35 is a simplified flow diagram of a method according toalternative lignin processing embodiments of the invention.

FIG. 36 is a simplified flow diagram of a method according toalternative lignin processing embodiments of the invention.

FIG. 37 is a plot of thermo-gravimetric analysis data (TGA) indicatingweight percent as a function of temperature for samples of high puritylignin according to exemplary embodiments of the invention incubated inN₂.

FIG. 38 is a plot of thermo-gravimetric analysis data (TGA) indicatingweight percent as a function of temperature for samples of lignin as inFIG. 37 incubated in air.

FIG. 39 is a simplified flow diagram of a method according to someexemplary lignin processing embodiments of the invention.

FIG. 40 is a simplified flow scheme of a method according to alternativelignin solubilization embodiments of the invention. PPTTP stands for“predetermined pressure-temperature-time profile.”

FIG. 41 is a simplified flow scheme of a method according to someexemplary lignin conversion processes.

FIG. 42A is a simplified flow schemes of method for treating cellulosepulp and residual lignin according to some embodiments of the invention;FIG. 42B shows glucose concentration in the solution at differentstarting cellulose pulp load in the reactor (10-20% wt dry solid); FIG.42C illustrates comparative saccharification of cellulose pulp obtainedby hemicelluloses extraction followed by acid/solvent lignin extraction(E-HDLM), and a commercial Sigmacell cotton linters.

FIG. 43 is a simplified flow scheme of a method according to alternativelignin solubilization embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION Introduction

The present invention relates to lignocellulosic biomass processing andrefining to produce hemicelluose sugars, cellulose sugars, lignin,cellulose and other high-value products.

An overview of the lignocellulosic biomass processing and refiningaccording to embodiments disclosed herein is provided in FIG. 17. Ingeneral, the lignocellulosic biomass processing and refining processesinclude: (1) pretreatment 1770; (2) hemicellulose sugar extraction 1700and purification 1710; (3) cellulose hydrolysis 1720 and cellulose sugarrefining 1730; (4) lignin processing 1740 and refining 1750; and (5)direct lignin extraction 1760.

Various products can be made using these processes. For example,hemicellulose sugar extraction 1700 and purification 1710 produce ahemicellulose sugar mixture, xylose, and a xylose-removed hemicellulosesugar mixture, as well as bioenergy pellets. Cellulose hydrolysis 1720and cellulose sugar refining 1730 processes produce a cellulose sugarmixture. Lignin processing 1740 and refining 1750 processes produce ahigh purity lignin and a high purity cellulose. Direct lignin extraction1760 process produces a high purity lignin.

The lignocellulosic biomass processing and refining begins withpretreatment 1770, during which the lignocellulosic biomass can be, forexample, debarked, chipped, shredded, dried, or grinded to particles.

During hemicellulose sugar extraction 1700, the hemicellulose sugars areextracted from the lignocellulosic biomass, forming an acidichemicellulose sugar stream 1700A and a lignocellulosic remainder stream1700B. The lignocellulosic remainder stream 1700B consists of mostlycellulose and lignin. It was surprisingly discovered in the presentinvention that hemicellulose sugars can be effectively extracted andconverted into monomeric sugars (e.g., >90% of the total sugar) bytreating biomass under mild conditions, e.g., with an acid in lowconcentrations, heat, and optionally pressure.

The acidic hemicellulose sugar stream 1700-A is purified inhemicellulose sugar purification 1710, acids and impurities co-extractedwith hemicellulose sugars can be easily removed from the hemicellulosesugar stream by solvent extraction (see FIG. 18 for more details, e.g.,amine extraction 1831 in FIG. 18). Once acids and impurities are removedfrom the hemicellulose sugar stream, the stream is neutralized andoptionally evaporated to a higher concentration. A high purityhemicellulose sugar mixture 1710-P1 is obtained, which can befractionated to obtain xylose and xylose-removed hemicellulose sugarmixture 1710-P3. Xylose is then crystallized to obtain xylose 1710-P2.

The lignocellulosic remainder 1700-B contains mostly cellulose andlignin. In some methods, the lignocellulosic remainder 1700-B can beprocessed to make bioenergy pellets 1700-P, which can be burnt as fuels.

In some methods, the lignocellulosic remainder 1700-B can be directlyprocessed to extract lignin. This process produces a high purity lignin1760-P1 and a high purity cellulose 1760-P2. The novel ligninpurification process of the invention utilizes a limited-solubilitysolvent, and can produce a lignin having a purity greater than 99%.

In some methods, the lignocellulosic remainder 1700-B can be subject tocellulose hydrolysis 1720 to obtain cellulose sugar mixture 1730-Pcontaining mostly C6 sugars. The novel cellulose hydrolysis processdescribed herein allows cellulose hydrolysis of differentlignocellulosic materials using a same set of equipment. Cellulosehydrolysis 1720 of the lignocellulosic remainder 1700-B results in anacidic hydrolysate stream 1720-A and an acidic lignin stream 1720-B.

The acidic hydrolysate stream 1720-A is then subject to cellulose sugarrefining 1730 (see FIG. 19 for more details, e.g., cellulose sugarrefining 1920 in FIG. 19). The acids in the acidic hydrolysate stream1720-A can be removed using a novel solve extraction system. Thedeacidified main sugar stream is further fractionated to removeoligosaccharides from monosaccharides. The acid can be recovered and thesolvents can be purified and recycled. The resulting cellulose sugarmixture 1730-P has unusually high monomeric sugar contents, particularlya high glucose content.

Acidic lignin stream 1720-B is subject to lignin processing 1740 andlignin refining 1750 to obtain high purity lignin 1750-P (see FIGS.20-21 for more details). Raw lignin stream 1720-B is first processed toremove any residual sugar and acids during lignin processing 1740. Thedeacidified lignin 1740-A is purified to obtain high purity lignin(lignin refining 1750). The novel lignin purification process of theinvention utilizes a limited-solubility solvent, and can produce alignin having a purity greater than 99%.

The sections I-VIII below illustrate lignocellulosic biomass processingand refining according to some embodiments disclosed herein. Section Idiscusses pretreatment 1770. Sections II and III discuss hemicellulosesugar extraction 1700 and purification 1710. Sections IV and V discusscellulose hydrolysis 1720 and cellulose sugar refining 1730. Section VIand VII discuss lignin processing 1740 and refining 1750. Section VIIIdiscusses direct lignin extraction 1760.

I. Pretreatment

Prior to hemicellulose sugar extraction 1700, lignocellulosic biomasscan be optionally pre-treated. Pretreatment refers to the reduction inbiomass size (e.g., mechanical breakdown or evaporation), which does notsubstantially affect the lignin, cellulose and hemicellulosecompositions of the biomass. Pretreatment facilitates more efficient andeconomical processing of a downstream process (e.g., hemicellulose sugarextraction). Preferably, lignocellulosic biomass is debarked, chipped,shredded and/or dried to obtain pre-treated lignocellulosic biomass.Pretreatment can also utilize, for example, ultrasonic energy orhydrothermal treatments including water, heat, steam or pressurizedsteam. Pretreatment can occur or be deployed in various types ofcontainers, reactors, pipes, flow through cells and the like. In somemethods, it is preferred to have the lignocellulosic biomass pre-treatedbefore hemicellulose sugar extraction 1700. In some methods, nopre-treatment is required, i.e., lignocellulosic biomass can be useddirectly in the hemicellulose sugar extraction 1700.

Optionally, lignocellulosic biomass can be milled or grinded to reduceparticle size. In some embodiments, the lignocellulosic biomass isgrinded such that the average size of the particles is in the range of100-10,000 micron, preferably 400-5,000, e.g., 100-400, 400-1,000,1,000-3,000, 3,000-5,000, or 5,000-10,000 microns. In some embodiments,the lignocellulosic biomass is grinded such that the average size of theparticles is less than 10,000, 9,000, 8,000, 7,000, 6,000, 5,000, 4,000,3,000, 1,000, or 400.

II. Hemicellulose Sugar Extraction

The present invention provides an advantageous method of extractinghemicellulose sugars from lignocellulosic biomass (hemicellulose sugarextraction 1700). Preferably, an aqueous acidic solution is used toextract lignocellulose biomass. The aqueous acidic solution can containany acids, inorganic or organic. Preferably, an inorganic acid is used.For example, the solution can be an acidic aqueous solution containingan inorganic or organic acid such as H₂SO₄, H₂SO₃ (which can beintroduced as dissolved acid or as SO₂ gas), HCl, and acetic acid. Theacidic aqueous solution can contain an acid in an amount of 0 to 2% acidor more, e.g., 0-0.2%, 0.2-0.4%, 0.4-0.6%, 0.6-0.8%, 0.8-1.0%, 1.0-1.2%,1.2-1.4%, 1.4-1.6%, 1.6-1.8%, 1.8-2.0% or more weight/weight.Preferably, the aqueous solution for the extraction includes 0.2-0.7%H₂SO₄ and 0-3,000 ppm SO₂. The pH of the acidic aqueous solution can be,for example, in the range of 1-5, preferably 1-3.5.

In some embodiments, an elevated temperature or pressure is preferred inthe extraction. For example, a temperature in the range of 100-200° C.,or more than 50° C., 60° C., 70° C., 80° C., 90° C., 100° C., 110° C.,120° C., 130° C., 140° C., 150° C., 160° C., 170° C., 180° C., 190° C.,or 200° C. can be used. Preferably, the temperature is in the range of110-160° C., or 120-150° C. The pressure can be in the range of 1-10mPa, preferably, 1-5 mPa. The solution can be heated for 0.5-5 hours,preferably 0.5-3 hours, 0.5-1 hour, 1-2 hours, or 2-3 hours, optionallywith a cooling down period of one hour.

Impurities such as ash, acid soluble lignin, fatty acids, organic acidssuch as acetic acid and formic acid, methanol, proteins and/or aminoacids, glycerol, sterols, rosin acid and waxy materials can be extractedtogether with the hemicellulose sugars under the same conditions. Theseimpurities can be separated from the aqueous phase by solvent extraction(e.g., using a solvent containing amine and alcohol).

After the hemicellulose sugar extraction 1700, the lignocellulosicremainder stream 1700-B can be separated from the acidic hemicellulosesugar steam 1700-A by any relevant means, including, filtration,centrifugation or sedimentation to form a liquid stream and a solidstream. The acidic hemicellulose sugar steam 1700-A containshemicellulose sugars and impurities. The lignocellulosic remainderstream 1700-B contains predominantly cellulose and lignin.

The lignocellulosic remainder stream 1700-B can be further washed torecover additional hemicellulose sugars and acidic catalyst trappedinside the biomass pores. The recovered solution can be recycled back tothe acidic hemicellulose sugar stream 1700-A, or recycled back to thehemicellulose sugar extraction 1700 reactor. The remaininglignocellulosic remainder stream 1700-B can be pressed mechanically toincrease solid contents (e.g., dry solid contents 40-60%). Filtrate fromthe pressing step can be recycled back to the acidic hemicellulose sugarstream 1700-A, or recycled back to the hemicellulose sugar extraction1700 reactor. Optionally, the remaining lignocellulosic remainder 1700-Bis grinded to reduce particle sizes. Optionally, the pressedlignocellulosic remainder is then dried to lower the moisture content,e.g., less than 15%. The dried matter can be further processed toextract lignin and cellulose sugars (processes 1720 and 1760 in FIG.17). Alternatively, the dried matter can be pelletized into pellets1700-P, which can be burnt as energy source for heat and electricityproduction or can be used as feedstock for conversion to bio oil.

Alternatively, the lignocellulosic remainder stream 1700-B can befurther processed to extract lignin (process 1760 in FIG. 17). Prior tothe lignin extraction, the lignocellulosic remainder stream 1700-B canbe separated, washed, and pressed as described above.

It was surprisingly found that hemicellulose sugar extraction 1700 canproduce, in one single extraction process, a hemicellulose sugar streamcontaining at least 80-95% monomeric sugars. For example, thehemicellulose sugar stream can contain more than 80%, 85%, 90%, 91%,92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% monomeric sugars. In addition,the present method produces minimal amounts of lignocellulosedegradation products such as furfural, levulinic acid, and formic acid.In addition, a xylose yield greater than 93% of theoretical value can beachieved. Overall, 18-27% of total sugars and at least 70%, 75%, or 80%or more of the hemicellulose sugars can be extracted using the presentmethod.

The acidic hemicellulose sugar stream 1700-A is then subject tohemicellulose sugar purification 1710. Various hemicellulose sugarproducts can be obtained from the purification. Exemplary purifiedproducts include hemicellulose sugar mixture 1710-P1, xylose 1710-P2,and xylose-removed hemicellulose sugar mixture 1710-P3.

III. Hemicellulose Sugar Purification

Prior to hemicellulose sugar purification 1710, the acidic hemicellulosesugar stream 1700-A from the hemicellulose sugar extraction 1700 can beoptionally filtered, centrifuged, or concentrated by evaporation. Forexample, the hemicellulose sugar stream can be contacted with strongacid cation exchanger (e.g., in H⁺ form) to convert all salts to theirrespective acids.

The hemicellulose sugar purification is illustrated in greater detailsaccording to an exemplary embodiment of the present invention as shownin FIG. 18. As illustrated in FIG. 18, the acidic hemicellulose sugarstream 1800-A is first subject to a strong cation exchange resin andthen amine extraction 1831, during which acids and impurities areextracted from the hemicellulose sugar stream into the amine extractant.The acids-depleted hemicellulose sugar stream 1831-A is then purified byion exchange 1832, including a strong acid cation exchanger 1833 andoptionally followed by a weak base anion exchanger 1834. Theamine-removed and neutralized hemicellulose sugar stream 1832-A isoptionally evaporated 1835 to form a hemicellulose sugar mixture 1836.Optionally, the amine removed and neutralized hemicelluloses sugarstream 1832-A may also be refined by contact with granulated activatedcarbon prior to evaporation 1835.

The hemicellulose sugar mixture 1836 can be optionally fractionated(process 1837 in FIG. 18) to obtain high purity C5 sugars such asxylose. Fractionation can be carried out by any means, preferably usinga simulated moving bed (SMB) or sequential simulated moving bed (SSMB).Examples of simulated moving bed processes are disclosed, for instance,in U.S. Pat. No. 6,379,554, U.S. Pat. No. 5,102,553, U.S. Pat. No.6,093,326, and U.S. Pat. No. 6,187,204, examples of sequential simulatedmoving bed processes can be found in GB 2 240 053 and U.S. Pat. No.4,332,623 as well as U.S. Pat. Nos. 4,379,751 and 4,970,002, each of thecontents of the entirety of which is incorporated herein by thisreference. In an exemplary SMB or SSMB setup, resin bed is divided intoa series of discrete vessels, each of which sequence through a series of4 zones (feed, separation, feed/separation/raffinate and safety) andconnected by a recirculation loop. A manifold system connects thevessels and directs, in appropriate sequence to (or from) each vessel,each of the four media accommodated by the process. Those media aregenerally referred to as feed, eluent, extract and raffinate. Forexample, a feed can be hemi cellulose sugar mixture 1836, the eluent canbe water, the extract is an enriched solution of xylose and theraffinate is an aqueous solution containing high molecular weight sugarsand other monomeric sugars i.e. arabinose, galactose and glucose.Optionally, the eluent can be an aqueous solution comprising lowconcentration of hydroxide ion to maintain the resin in hydroxyl form,or the eluent can be an aqueous solution comprising low concentration ofacid to maintain the resin in a protonated form. For example, a feedcomprising 30% sugar mix where xylose is about 65-70% of the mix can befractionated using a SSMB to obtain an extract comprising about 16-20%sugars where xylose is about 82% or more and a raffinate comprising 5-7%sugar mix with only 15-18% xylose.

When a SSMB is used for fractionation, xylose exits from the extractflow and the higher sugars as well as glucose, galactose and arabinoseexit from the raffinate flow. The xylose stream 1837-A can optionally berefined by contacting with granulated activated carbon and refined withmixed bed prior to evaporation to higher concentration (process 1838 inFIG. 18). The refined xylose stream 1839-A is then optionally evaporatedagain and crystallized (see, e.g., processes denoted in FIG. 18 by thenumber 1841). The products are xylose crystal 1842 and xylose-removedhemicellulose sugar mixture 1843.

The amine extractant stream 1831-A can be back-extracted with an aqueoussolution containing a base (e.g., sodium hydroxide, sodium carbonate,and magnesium hydroxide) (see, e.g., process denoted in FIG. 18 by thenumber 1850). A portion of the solvent can be further purified using alime solution (e.g. calcium oxide, calcium hydroxide, calcium carbonate,or a combination thereof) (see, e.g., process denoted in FIG. 18 by thenumber 1860) and the purified solvent can be recycled back to the amineextraction 1831.

Specific Embodiments of Hemicellulose Sugar Purification (FIGS. 1-7)

Several preferred embodiments of hemicellulose sugar purification areillustrated in FIGS. 1-7. In FIG. 1, during hemicellulose sugarextraction 101, at least portion of the hemicellulose and impurities areextracted from lignocellulosic biomass by liquid extracting (e.g., usingan acidic aqueous solution) to produce an acidic hemicellulose sugarstream and a lignocellulosic remainder stream. In some embodiments,hemicellulose sugar extraction 101 employs pressure cooking (e.g.,120-150° C., 1-5 mPa). The acidic hemicellulose sugar stream issubjected to amine extraction 102 using an amine extractant containingan amine having at least 20 carbon atoms, resulting in an acid-depletedhemicellulose sugar stream and an amine extractant stream. In oneexample, the amine extractant stream is subjected to a water washfollowed by back extraction 103 with a base. At least a portion of theamine extractant stream is then subject to purification and filtration104 before it is recycled back to amine extraction 102. The other partof the stream may be returned directly for reuse in amine extraction102.

In FIG. 2, at least a portion of the hemicellulose and impurities areextracted in hemicellulose sugar extraction 201 by liquid extracting(e.g., using an acidic aqueous solution). In some embodiments,hemicellulose sugar extraction 201 produces an acidic hemicellulosesugar stream and a lignocellulosic remainder stream. In someembodiments, hemicellulose sugar extraction 201 employs pressurecooking. In some embodiments, the acidic hemicellulose sugar stream issubjected to amine extraction 202 using an amine extractant containingan amine having at least 20 carbon atoms, resulting in an acid-depletedhemicellulose sugar stream and an amine extractant stream. The amineextractant stream is subjected to a water wash followed by a backextraction 203 with a base. At least a portion of the amine extractantstream is then subject to purification and filtration 204 before it isrecycled for reuse in amine extraction 202. The other part of the streammay be returned directly for reuse in the amine extraction 202. Theaqueous stream resulting from the back extraction 203 is subjected to acation exchange 205 and then to a distillation 206. In some embodimentsdistillation 206 produces acids.

In FIG. 3, at least portion of the hemicellulose and impurities areextracted in hemicellulose sugar extraction 301 by liquid extracting(e.g., using an acidic aqueous solution) to produce an acidichemicellulose sugar stream and a lignocellulosic remainder stream. Insome embodiments, hemicellulose sugar extraction 301 employs pressurecooking. In some embodiments, the acidic hemicellulose sugar stream issubjected to amine extraction 302 using an amine extractant containingan amine having at least 20 carbon atoms, resulting in an acid-depletedhemicellulose sugar stream and an amine extractant stream. In someembodiments, the amine extractant stream is subjected to a water washfollowed by back extraction 303 with a base. At least a portion of theamine extractant stream is then subject to purification and filtration304 before reuse in amine extraction 302. The other part of the streammay be returned directly to reuse in amine extraction 302. Thelignocellulose remainder stream is dried, milled if required andpelletized to produce lignocellulose pellets (process 310 in FIG. 3).

In FIG. 4, at least portion of the hemicellulose and impurities areextracted in hemicellulose sugar extraction 401 by liquid extracting(e.g., using an acidic aqueous solution) to produce an acidichemicellulose sugar stream and a lignocellulosic remainder stream. Insome embodiments, hemicellulose sugar extraction 401 employs pressurecooking. In some examples, the acidic hemicellulose sugar stream issubjected to amine extraction 402 using an amine extractant containingan amine having at least 20 carbon atoms, resulting in an acid-depletedhemicellulose sugar stream and an amine extractant stream. In someembodiments, the amine extractant stream is subjected to a water washfollowed by back extraction 403 with a base. At least a portion of theamine extractant stream is then subject to purification and filtration404 before reuse in amine extraction 402. The other part of the streammay be returned directly to reuse in amine extraction 402. Acid-depletedhemicellulose sugar stream is then subject to refining 407. In thedepicted example, the refined sugar stream is then concentrated inevaporator 410, followed by fractionation at 409 to yield a streamcontaining xylose at high concentration and a xylose-depletedhemicellulose sugar stream. The stream containing xylose at highconcentration is then crystallized 408 to make crystal sugar product.The resulting mother liquor is recycled to evaporator 410.

In FIG. 5, at least portion of the hemicellulose and impurities areextracted in hemicellulose sugar extraction 501 by liquid extracting(e.g., using an acidic aqueous solution) to produce an acidichemicellulose sugar stream and a lignocellulosic remainder stream. Insome embodiments, hemicellulose sugar extraction 501 employs pressurecooking. In some embodiments, the acidic hemicellulose sugar stream issubjected to amine extraction 502 using an amine extractant containingan amine having at least 20 carbon atoms, resulting in an acid-depletedhemicellulose sugar stream and an amine extractant stream. In someembodiments, the amine extractant stream is subjected to a water washfollowed by back extraction 503 with a base. At least a portion of theamine extractant stream is then subject to purification and filtration504 before reuse in amine extraction 502. The other part of the streammay be returned directly to reuse in amine extraction 502. Acid-depletedhemicellulose sugar stream is then subject to refining 507. In thedepicted example, the refined sugar stream is then concentrated inevaporator 510, followed by fractionation at 509 to yield a streamcontaining xylose at high concentration and a xylose-depletedhemicellulose sugar stream. The stream containing xylose at highconcentration is then crystallized (process 508) to make crystal sugarproduct. The resulting mother liquor is recycled to evaporator 510.

In FIG. 6, at least portion of the hemicellulose and impurities areextracted in hemicellulose sugar extraction 601 by liquid extracting(e.g., using an acidic aqueous solution) to produce an acidichemicellulose sugar stream and a lignocellulosic remainder stream. Insome embodiments, hemicellulose sugar extraction 601 employs pressurecooking. In some embodiments, the acidic hemicellulose sugar stream issubjected to amine extraction 602 using an amine extractant containingan amine having at least 20 carbon atoms, resulting in an acid-depletedhemicellulose sugar stream and an amine extractant stream. In someembodiments, the amine extractant stream is subjected to a water washfollowed by back extraction 603 with a base. At least a portion of theamine extractant stream is then subject to purification and filtration604 before reuse in amine extraction 602. The lignocellulosic remainderstream is milled and pelletized (process 610) to produce lignocellulosepellets. Acid-depleted hemicellulose sugar stream is then subject torefining 607. In the depicted example, the refined sugar stream is thenconcentrated in evaporator 610, followed by fractionation at 609 toyield a stream containing xylose at high concentration and axylose-depleted hemicellulose sugar stream. The stream containing xyloseat high concentration is then crystallized 608 to make crystal sugarproduct. The resulting mother liquor is recycled to evaporator 610.

FIG. 7 depicts a chromatographic fractionation of a refined sugar mix toobtain an enriched xylose fraction and a mix sugar solution containingglucose, arabinose and a variety of DP2+ components.

A more detailed description of these exemplary hemicellulose sugarpurification embodiments is provided below.

1. Amine Extraction

As discussed above, the hemicellulose sugar stream1800-A can beextracted with an amine extractant containing an amine base and adiluent, to remove mineral acid(s), organic acids, furfurals, acidsoluble lignins (see, e.g., the processes denoted in FIGS. 1-6 by thenumber X02, where X is 1, 2, 3, 4, 5, or 6 depending on the figures;process 1831 in FIG. 18). The extraction can be carried out by anymethod suitable for extracting acids. Preferably, the hemicellulosesugar stream 1800-A is extracted with an amine extractantcounter-currently, e.g., the hemicellulose sugar stream1800-A flows inan opposite direction to the flow of the amine extractant. Thecounter-current extraction can be carried out in any suitable device,e.g., a mixer-settler device, stirred tanks, columns, or any otherequipment suitable for this mode of extraction. Preferably, the amineextraction is conducted in a mixer-settler designed to minimize emulsionformation and reduce phase separation time. A mixer-settler has a firststage that mixes the phases together followed by a quiescent settlingstage that allows the phases to separate by gravity. Variousmixer-settlers known in the art can be used. In some methods, phaseseparation may be enhanced by incorporating a suitable centrifuge withthe mixer-settler.

Typically, the vast majority of the sugars remain in the acid-depletedhemicellulose sugar stream 1831-B, whereas much of the organic orinorganic acids (e.g., the acids used in hemicellulose sugar extraction)and impurities are extracted into the amine extractant stream 1831-A.The amine extractant stream 1831-A can be contacted with an aqueousstream in a counter current mode, to recover any residual sugarsabsorbed into the amine extractant stream. In some embodiments, theamine extractant stream 1831-A contains less than 5, 4, 3, 2, 1, 0.8,0.6, 0.5, 0.4, 0.2, 0.1% w/w hemicellulose sugars. In some embodiments,the acid-depleted hemicellulose sugar stream 1831-B contains less than5, 4, 3, 2, 1, 0.8, 0.6, 0.5, 0.4, 0.2, 0.1% w/w acid. In someembodiments, the acid-depleted hemicellulose sugar stream 1831-Bcontains less than 5, 4, 3, 2, 1, 0.8, 0.6, 0.5, 0.4, 0.2, 0.1% w/wamine. In some embodiments, the acid-depleted hemicellulose sugar stream1831-B contains less than 5, 4, 3, 2, 1, 0.8, 0.6, 0.5, 0.4, 0.2, 0.1%w/w impurities.

The amine extractant can contain 10-90% or preferably 20-60%weight/weight of one or a plurality of amines having at least 20 carbonatoms. Such amine(s) can be primary, secondary, and tertiary amines.Examples of tertiary amines include tri-laurylamine (TLA; e.g. COGNISALAMINE 304 from Cognis Corporation; Tucson Ariz.; USA), tri-octylamine,tri-isooctylamine, tri-caprylylamine and tri-decylamine.

Diluents suitable for use in the amine extraction include an alcoholsuch as butanol, isobutanol, hexanol, octanol, decanol, dodecanol,tetradecanol, pentadecanol, hexadecanol, octadecanol, eicosanol,docosanol, tetracosanol, and triacontanol. Preferably, the diluent is along chain alcohol (e.g. C6, C8, C10, C12, C14, C16 alcohol), orkerosene. The diluent can have additional components. More preferably,the diluent comprises n-hexanol or 2-ethyl-hexanol. Most preferably, thediluent comprises n-hexanol. In some embodiments, the diluent consistsessentially of or consists of n-hexanol.

Optionally, the diluent contains one or more additional components. Insome methods, the diluent contains one or more ketones, one or morealdehydes having at least 5 carbon atoms, or another alcohol.

Preferably, the amine is tri-laurylamine and the diluent is hexanol. Theratio of amine and diluent can be any ratio, e.g., between 3:7 and 6:4weight/weight. In some methods, the amine extraction solution containstri-laurylamine and hexanol in a ratio of 1:7, 2:7, 3:7, 6:4, 5.5:4.55,4:7, 5:7, 6:7, 7:7, 5:4, 3:4, 2:4, or 1:4 weight/weight. Preferably, theamine extraction solution contains tri-laurylamine and hexanol in aratio of 3:7 weight/weight.

The amine extraction can be conducted at any temperature at which theamine is soluble, preferably at 50-70° C. Optionally, more than oneextraction steps (e.g., 2, 3, or 4 steps) can be used. The ratio of theamine extractant stream (organic phase) to the hemicellulose sugarstream1800-A (aqueous phase) can be 0.5-5:1, 1-2.5:1, or preferably,1.5-3.0:1 weight/weight.

2. Back Extraction

The amine extractant stream 1831-A contains mineral and organic acid, aswell as impurities extracted from biomass and sugar degradationproducts. The acids can be extracted from the amine extractant stream1831-A in a back extraction step (see, e.g., the processes denoted inFIGS. 1-6 by the number X03, where X is 1, 2, 3, 4, 5, or 6respectively; process 1850 in FIG. 18).

Optionally, prior to the back extraction 1850, the amine extractantstream 1831-A can be washed with an aqueous solution to recover anysugars in the stream. Typically, after the washing, the amine extractantstream 1831-A has less than 5%, 2%, 1%, 0.5%, 0.2%, 0.1%, 0.05% sugars.

The back extraction medium is an aqueous solution containing a base. Forexample, the extraction medium can be a solution containing NaOH,Na₂CO₃, Mg(OH)₂, MgO, or NH₄OH. The concentration of the base can be1-20% by weight/weight, preferably 4-10% by weight/weight. Preferably,the base of choice produces a soluble salt when reacted with the acidsin the acid-loaded organic stream. Preferably, the amount of the base inthe back extraction medium is 2-10% excess over the stoichiometricequivalent of acids in the organic stream.

Back extraction 1850 can be carried out in any device, e.g., amixer-settler device, stirred tanks, columns, or any other equipmentsuitable for this mode of back extraction. Preferably, the backextraction is conducted in a mixer-settler designed to minimize emulsionformation and reduce phase separation time, e.g., a mixer-settlerequipped with low emulsifying mixers for high rate separation, or intandem with a centrifuge to enhance separation. Back extraction canresult in removal of at least 93% of the mineral acid and at least 85%of the organic acid from the organic phase.

Back extraction 1850 can be carried out in multiple reactors. In oneexample, back extraction 1850 is carried out in 4 reactors. In the firstreactor, the amount of base is equivalent to that of carboxylic acid andonly the carboxylic acids is back-extracted to produce a solution oftheir salt(s) (e.g. sodium salt). In the second reactor, the mineralacid is back-extracted. The streams coming out of each reactor istreated separately to allow recovering of the organic acids. Optionally,the aqueous streams coming out of the back extraction steps can becombined. Typically, the combined stream contains at least 3% of theanion of the mineral acid (e.g. sulfate ion if sulfuric and/or sulfurousacids where used in hemicellulose sugar extraction 1700), and 0.2-3%acetic acid as well as lower concentrations of other organic acids. Theaqueous stream can contain low concentration of the organic phasediluent, typically less than 0.5%, depending on the solubility of thediluent used in water. Preferably, the aqueous stream coming out of backextraction is kept to allow segregation of chemicals present in thesestreams. In one example, Ca²⁺ and SO₄ ²⁻, which are deleterious toanaerobic digestion, is routed separately to aerobic treatment.

The organic phase diluent may be removed from the aqueous phase bydistillation, where in many cases these diluents may form aheterogeneous azeotrope with water that has a lower boiling point thanthe diluent solvent alone, thus the energy required to distill off thediluent is significantly reduced due to the vast excess of water overthe diluent. The distilled solvent can be recovered and recycled backinto the solvent reservoir for further use. The diluent-stripped aqueousphase may be directed to the waste treatment unit of the plant.

3. Solvent Purification

The amine extractant stream, now neutralized after acid removal, can bewashed with water to remove salts remaining from the back extraction. Itis particularly preferred for certain blended extractants that canpartially saturate with water (as is the case of certain alcohols forexample). The wash stream may be combined with the back extractionaqueous stream. A fraction of the washed amine extractant, typically5-15% of the total weight of the amine extractant stream, can bediverted to the purification and filtration step denoted as X04 in FIGS.1-6 (see, also, process 1860 in FIG. 18). The remaining amine extractantis recycled to amine extraction denoted as X02 in FIGS. 1-6.

The fraction diverted to purification step (X04 in FIGS. 1-6; process1860 in FIG. 18) can be treated with a lime suspension (e.g., a 5%, 10%,15%, 20%, 25% weight/weight lime solution). The solvent to limesuspension ratio can be in the range 4-10, 4-5, 5-6, 6-7, 7-8, 8-9, or9-10. Treatment may be conducted in any suitable device, e.g., athermostatic mixed tank. The solution can be heated for at least 1 hourat 80-90° C. Lime reacts with residual organic acids and esters oforganic acids and adsorbs effectively organic impurities present in theorganic phase such as acid soluble lignin and furfurals, as visualizedby change of color from dark to light. The contaminated lime andimpurities can be filtered or centrifuged to recover the purifiedorganic phase, which is washed with water and recycled back to the amineextraction step (X02 in FIGS. 1-6; process 1831 in FIG. 18). The aqueousstream may be diverted to other aqueous waste streams. Any solid cakethat may be formed by the lime reaction may be used in the waste watertreatment plant as a neutralization salt for residual acids from ionexchange regenerations for example.

The back extraction aqueous stream contains salts of the organic acids.This stream can be contacted with a cation exchanger to convert allsalts to their respective organic acids (see, e.g., the processesdenoted in FIGS. 2, 5 and 6 by the number X05 where X is 2, 5, or 6respectively). Alternatively the organic acids can be converted to theacid form by acidifying the solution with a strong mineral acid. Theacidified stream can be distilled to harvest formic acid and acetic acid(see, e.g., the processes denoted in FIGS. 2, 5 and 6 by the number X06where X is 2, 5, or 6 respectively). Remaining aqueous streams arediverted to waste.

4. Sugar Purification

The acid-depleted hemicellulose sugar stream can be further purified(see, e.g., FIGS. 4-6). For example, the diluent in the acid-depletedhemicellulose sugar stream can be removed using a packed distillationcolumn. The distillation can remove at least 70%, 80%, 90%, or 95% ofthe diluent in the acid-depleted hemicellulose sugar stream. With orwithout diluent distillation step, the acid-depleted hemicellulose sugarstream can also be contacted with a strong acid cation (SAC) exchangerto remove any residual metallic cations and any residual amines.Preferably, the acid-depleted hemicellulose sugar stream is purifiedusing a packed distillation column followed by a strong acid cationexchanger.

Preferably, the acid-depleted hemicellulose sugar stream can then becontacted with a weak base anion (WBA) exchanger to remove excessprotons. The amine-removed and neutralized hemicellulose sugar streamcan be pH adjusted and evaporated to 25-65% and preferably 30-40%weight/weight dissolved sugars in any conventional evaporator, e.g., amultiple effect evaporator or a mechanical vapor recompression (MVR)evaporator.

Any residual solvent present in the hemicellulose sugar stream can alsobe removed by evaporation. For example, the solvent that forms aheterogeneous azeotrope with water can be separated and returned to thesolvent cycle. Optionally the concentrated sugar solution can becontacted with activated carbon to remove residual organic impurities.The concentrated sugar solution may also be contacted with mixed bedresin system to remove any residual ions or color bodies. Optionally,the now refined sugar solution can be concentrated further by andconventional evaporator or MVR.

The resulting stream is a highly purified hemicellulose sugar mixture(e.g., 1836 in FIG. 18) comprising, e.g., 85-95% weight/weightmonosaccharides out of the total dissolved sugars. The composition ofthe sugars depends on the composition of the starting biomass. Ahemicellulose sugar mixture produced from softwood biomass can have65-75% (weight/weight) C6 saccharides in the sugar solution out of totalsugars. In contrast, a hemicellulose sugar mixture produced fromhardwood biomass can contain 80-85% weight/weight C6 sugars out of totalsugars. The purity of the stream in all cases may be sufficient forfermentation processes and/or catalytic processes utilizing thesesugars.

The highly purified hemicellulose sugar mixture 1836 is characterized byone or more, two or more, three or more, four or more, five or more, sixor more characteristics including (i) monosaccharides in a ratio tototal dissolved sugars >0.50 weight/weight; (ii) glucose in a ratio tototal monosaccharides <0.25 weight/weight; (iii) xylose in a ratio tototal monosaccharides >0.18 weight/weight; (iv) fructose in a ratio tototal monosaccharides <0.10 weight/weight; (v) fructose in a ratio tototal monosaccharides >0.01 weight/weight; (vi) furfurals in amount upto 0.01% weight/weight; (vii) phenols in amounts up to 500 ppm; and(viii) a trace amount of hexanol. For example, the sugar mixture can bea mixture having a high monosaccharides to total dissolved sugars ratio,a low glucose content, and a high xylose content. In some embodiments,the sugar mixture is a mixture having a high monosaccharides to totaldissolved sugars ratio, a low glucose content, a high xylose content,and a low impurity contents (e.g., low furfurals and phenols). In someembodiments, the mixture is characterized by a high monosaccharides tototal dissolved sugars ratio, a low glucose content, a high xylosecontent, a low impurity contents (e.g., low furfurals and phenols), anda trace amount of hexanol.

In some embodiments, the resulting stream is a sugar mixture with a highmonomeric ratio. In some sugar mixture, monosaccharides to totaldissolved sugars ratio is larger than 0.50, 0.60, 0.70, 0.75, 0.80,0.85, 0.90, or 0.95 weight/weight. In some embodiments, the resultingstream is a sugar mixture having a low glucose content. In some sugarmixture, the glucose to total monosaccharides ratio is less than 0.25,0.20, 0.15, 0.13, 0.10, 0.06, 0.05, 0.03, or 0.02 weight/weight. In someembodiments, the resulting stream is a sugar mixture with a high xylosecontent. In some sugar mixture, the xylose to total monosaccharidesratio is larger than 0.10, 0.15, 0.18, 0.20, 0.30, 0.40, 0.50, 0.60,0.70, 0.80 or 0.85 weight/weight.

In some sugar mixtures 1836, the fructose to total dissolved sugarsratio is less than 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10,0.15, 0.20, 0.25 or 0.30 weight/weight. In some sugar mixtures 1836, thefructose to total dissolved sugars ratio is larger than 0.001, 0.002,0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06,0.07, 0.08, or 0.09 weight/weight.

The above hemicellulose sugar mixture includes a very low concentrationof impurities (e.g., furfurals and phenols). In some resulting stream,the sugar mixture has furfurals in an amount up to 0.1%, 0.05%, 0.04%,0.03%, 0.04%, 0.01%, 0.075%, 0.005%, 0.004%, 0.002%, or 0.001%weight/weight. In some resulting stream, the sugar mixture has phenolsin an amount up to 500 ppm, 400 ppm, 300 ppm, 200 ppm, 100 ppm, 60 ppm,50 ppm, 40 ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm, 1 ppm, 0.1 ppm, 0.05 ppm,0.02 ppm, or 0.01 ppm. The hemicellulose sugar mixture is furthercharacterized by a trace amount of hexanol, e.g., 0.01-0.02%,0.02-0.05%, 0.05-0.1%, 0.1%-0.2%, 0.2-0.5%, 0.5-1%, or less than 1, 0.5,0.2, 0.1, 0.05, 0.02, 0.01, 0.005, 0.002, 0.001%, weight/weight hexanol.

This high purity sugar solution can be used to produce industrialproducts and consumer products as described in PCT/IL2011/00509(incorporated herein by reference for all purposes). Furthermore, thesoftwood sugar product containing 65-75% weight/weight C6 sugars can beused as fermentation feed to species that are only able to utilize C6sugars, and the resulting mix of C5 and product may be separated, the C5can then be refined to obtain a C5 product, as described inPCT/US2011/50435 (incorporated herein by reference for all purposes).

Fermentation product includes at least one member selected from thegroup consisting of alcohols, carboxylic acids, amino acids, monomersfor the polymer industry and proteins and wherein the method furthercomprises processing said fermentation product to produce a productselected from the group consisting of detergent, polyethylene-basedproducts, polypropylene-based products, polyolefin-based products,polylactic acid (polylactide)-based products, polyhydroxyalkanoate-basedproducts and polyacrylic-based products.

These fermentation products may be used alone or with other componentsas food or feed, pharmaceuticals, nutraceuticals, plastic parts orcomponents to make various consumer products, fuel, gasoline, chemicaladditive or surfactant.

The high purity sugar solution products are suitable for chemicalcatalytic conversions since catalysts are usually sensitive toimpurities associated with biomass and sugar degradation products.Typically, the purity is greater than 95, 96, 97, 98%, preferablygreater than 99, 99.5, or 99.9%. This product contains small amounts ofmarker molecules including for example residual diluent, e.g. hexanol,1-ethyl hexanol, kerosene or any other diluents used, as well asfurfural, hydroxymethylfurfural, products of furfural orhydroxymethylfurfural condensation, color compounds derived from sugarcaramelization, levulinic acid, acetic acid, methanol, galacturonic acidor glycerol.

5. Sugar Fractionation

Some biomass materials contain a high concentration of a single sugar aspart of their hemicellulosic sugar composition. For example, eucalyptusand bagasse contain high concentration of xylose. A single sugar such asxylose has specific application and much greater industrial value ascompared to a sugar mixture. Therefore, it is highly beneficial tofractionate the sugar stream to obtain a high concentration of thesingle sugar to facilitate sugar crystallization and production of highpurity single sugar product.

The hemicellulose sugar mixture 1836 can be optionally concentrated byevaporation, and fractionated 1837 (e.g., by chromatographic separation)to produce a xylose-enriched stream 1837-A having more than 75, 78, 80,82, 84, 85, 86, 88, 90% xylose, and a xylose-removed hemicellulose sugarmixture 1837-B. The xylose-removed hemicellulose sugar mixture 1837-Bcan be used as substrate for fermentation processes that are capable offermenting C5/C6 sugar mixtures, as substrate for chemical conversion,or as substrate for anaerobic digestion to produce energy.

The chromatographic fractionation to achieve enrichment of xyloseconcentration can be carried out with ion exchange resins (e.g., acation exchange resin and an anion exchange resin) as the column fillingmaterial. The cation exchange resins include strong acid cation exchangeresins and weak acid cation exchange resins. The strong acid cationexchange resins can be in a monovalent or multivalent metal cation form,e.g., in H⁺, Mg²⁺, Ca²⁺ or Zn²⁺ form. Preferably, the resins are in Naform. The strong acid cation exchange resins typically have a styreneskeleton, which is preferably cross-linked with 3 to 8%, preferably 5 to6.5% of divinylbenzene. The weak acid cation exchange resins may be in amonovalent or multivalent metal cation form, e.g., H⁺, Mg²⁺ or Ca²⁺form, preferably in Na form.

The chromatographic fractionation can be carried out in a batch mode ora simulated moving bed (SMB) mode or a sequential simulated moving bed(SSMB) mode. The temperature of the chromatographic fractionation istypically in the range of 20 to 90° C., preferably 40 to 65° C. The pHof the solution to be fractionated can be acidic or adjusted to a rangeof 2.5-7, preferably 3.5-6.5 and most preferably 4-5.5. Typically, thefractionation can be carried out with a linear flow rate of about 1m/h-10 m/h in the separation column.

Anion exchange resins have usually been used in the past fordemineralization of solutions, i.e., for ion exchange, or fordecolorization, i.e., for adsorption. In some embodiments of theinvention, there can be little or no net ion exchange or adsorptionbetween the resin and the solution. In that case, an anion-type ionexchange resin is used for its properties as a chromatographicsubstrate, rather than in a column intended primarily for net exchangeof ions.

Chromatographic separation differs from other column-based separations(e.g., ion-exchange or adsorption) in that no major component in thefeed mixture is retained by the sorbent so strongly as to require thatadditional reagents be routinely used between cycles to regenerate thecolumn by removing strongly retained components before the nextseparation cycle. In general, a chromatographic column can be re-usedfor multiple cycles before regeneration before the columns require somedegree of periodic cleansing or regeneration. The function of anion-exchange or adsorption column is to bind components tightly,necessarily requiring frequent regeneration for the resin to be reused.By contrast, the function of a chromatographic column is to providedifferential mobility for components moving through the column to effecta separation, but not to bind too tightly to the principal components.Regeneration of a chromatographic column may be needed from time to timedue to incidental binding of minor components or impurities to theresin. The minimal quantity of reagents needed for resin regeneration isa major advantage of chromatographic separations over ion-exchangeseparations. The operational cost of chromatographic separations is dueprimarily to the energy needed to evaporate water (or other solvent)from dilute products, and to a lesser extent to the infrequentreplacement or regeneration of resin.

A preferred method for large-scale chromatographic separations is thesequential simulated moving bed (SSMB), or alternatively a simulatedmoving bed (SMB). Both methods use a number of columns packed with asuitable sorbent and connected in series. There are inlet ports for feedand solvent (which may include recycled solvent), and outlet ports fortwo or more products (or other separated fractions). The injection ofthe mixture solution to be separated is periodically switched betweenthe columns along the direction of the liquid flow, thereby simulatingcontinuous motion of the sorbent relative to the ports and to theliquid. The SMB is a continuous counter current type operation. SSMB isa more advance method, requiring a sequential operation. Its advantagesover SMB and over other older methods include: fewer number of columnsis needed in the SSMB method versus the SMB, hence less resin isrequired and hence associated cost of installation is significantlyreduced in large system; the pressure profile is better controlled,facilitating the use of more sensitive resins; achievablerecovery/purity is higher than obtained with SMB systems.

Fractionation of xylose from the refined mix sugar solution X09 (Xdenotes 4, 5, or 6 in FIGS. 4-6; process 1837 in FIG. 18) can bepreferably achieved using a strong base anion (SBA) exchanger having aparticle size of ˜280-320 μm. This larger particle size is advantageousover much smaller particles sizes used in U.S. Pat. No. 6,451,123. Alarger particle size reduces the back pressure of the column toindustrially practical range. Suitable commercial SBA resins can bepurchased from Finex (AS 510 GC Type I, Strong Base Anion, gel form),similar grades can be purchased from other manufacturers includingLanxess AG, Purolite, Dow Chemicals Ltd. or Rohm & Haas. The SBA resinmay be in the sulfate or chloride form, preferably in the sulfate form.The SBA is partially impregnated with hydroxyl groups by lowconcentration NaOH, the range of base to sulfate is 3-12% to 97-88%respectively. To maintain this level of OH groups on the resin, a lowlevel of NaOH, sufficient to replace the hydroxyl removed by sugaradsorption, may be included in the desorption pulse, thus making thexylose retain longer than other sugars on this resin. Fractionation maybe conducted in the SSMB mode at about 40-50° C., resulting in a xyloserich stream, containing at least 79%, at least 80%, at least 83%,preferably at least 85% xylose out of total sugars, and a mix sugarstream, at a recovery of at least 80%, at least 85% xylose.

In some methods, the SSMB sequence includes three steps. In the firststep, a product stream is extracted by exposing and flushing theadsorbent with a desorbent stream (“desorbent to extract” step).Concurrently, a feed stream in passed into the adsorbent and a raffinatestream is flushed from the adsorbent (“feed to raffinate” step). In thesecond step, a raffinate stream is extracted by exposing and flushingthe adsorbent with a desorbent stream (“desorbent to raffinate” step).In the third step, the desorbent is recycled back to the adsorbent(“recycle” step).

Typically, the product is extracted in such a manner that the raffinateflow equals the desorbent flow but it results in a high desorbentconsumption to reach the target product recovery. Preferably, in someSSMB sequences, the product is extracted in more than one step (e.g.,not only in step 1, but also in step 2). In some methods, the productstream is not only extracted in the first step, but also extracted inthe second step (i.e., the “desorbent to raffinate” step). When theproduct is extracted in more than one step, the desorbent flow rate isequal to the sum of the extract flow rate and the raffinate flow rate.In some embodiments, the desorbent flow rate is about the same as thesum of the extract flow rate and the raffinate flow rate. In someembodiments, the desorbent flow rate is within 50-150%, 60-140%,70-130%, 80-120%, 90-110%, 95-105%, 96-104%, 97-103%, 98-102%, 99-101%,or 99.5-100.5%, of the sum of the extract flow rate and the raffinateflow rate. This change in the SSMB sequence decreases the requireddesorbent, resulting in the target product recovery with much lessdesorbent volume while maintaining the SSMB chromatographic profiles inthe four (4) zones and six (6) columns and purity.

Following fractionation X09 the sugar streams can optionally becontacted with a weak acid cation (WAC) exchange resin in the H+ form toneutralize the sugar stream. This acidification allows evaporation ofthe sugar stream while maintaining sugar stability. The WAC resin can beregenerated by a mineral acid or preferably by contacting with the wasteacid stream of the SAC resin used at the sugar refining step X07 (Xdenotes 4, 5, or 6 in FIGS. 4-6). Following the WAC neutralization step,the mix sugar stream can optionally be directed to evaporator X10 (Xdenotes 4, 5, or 6 in FIGS. 4-6), while the xylose rich stream isdirected to the sugar crystallizer X08 (X denotes 4, 5, or 6 in FIGS.4-6).

The xylose-enriched stream 1837-A is characterized by one or more, twoor more, three or more, four or more, five or more, six or more, sevenor more, eight or more, nine or more, ten or more characteristicsincluding (i) oligosaccharides in a ratio to total dissolved sugars<0.10 weight/weight; (ii) xylose in a ratio to total dissolvedsugars >0.50 weight/weight; (iii) arabinose in a ratio to totaldissolved sugars <0.10 weight/weight; (iv) galactose in a ratio to totaldissolved sugars <0.05 weight/weight; (v) the sum of glucose andfructose in a ratio to total dissolved sugars <0.10 weight/weight; (vi)mannose in a ratio to total dissolved sugars <0.02 weight/weight; (vii)fructose in a ratio to total dissolved sugars <0.05 weight/weight;(viii) furfurals in an amount up to 0.01% weight/weight; (ix) phenols inan amount up to 500 ppm; and (x) a trace amount of hexanol. For example,the sugar mixture 1837-A is a mixture characterized a lowoligosaccharides to total dissolved sugars ratio and a high xylose tototal dissolved sugars ratio. In some embodiments, the sugar mixture1837-A is a mixture characterized by a low oligosaccharides to totaldissolved sugars ratio, a high xylose to total dissolved sugars ratio,and a low impurity contents (e.g., low furfurals and phenols). In someembodiments, the sugar mixture 1837-A is a mixture characterized by alow oligosaccharides to total dissolved sugars ratio, a high xylose tototal dissolved sugars ratio, a low impurity contents (e.g., lowfurfurals and phenols), and a trace amount of hexanol. In someembodiments, the sugar mixture 1837-A is a mixture characterized by alow oligosaccharides to total dissolved sugars ratio, a high xylose tototal dissolved sugars ratio, a low ratio of the sum of glucose andfructose to total dissolved sugars ratio, a low impurity contents (e.g.,low furfurals and phenols), and a trace amount of hexanol.

In some embodiments, the xylose-enriched stream 1837-A is a sugarmixture characterized by a high xylose to total dissolved sugars ratio.In some sugar mixtures, the xylose to total dissolved sugars ratio islarger than 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85,or 0.90 weight/weight. In some embodiments, the xylose-enriched stream1837-A is a sugar mixture characterized by a low oligosaccharides tototal dissolved sugars ratio. In some sugar mixtures, theoligosaccharides to total dissolved sugars ratio is less than 0.002,0.005, 0.007, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09,0.10, 0.20, or 0.30 weight/weight. In some embodiments, thexylose-enriched stream 1837-A is a sugar mixture with a lowglucose/fructose content. In some sugar mixtures, the ratio of the sumof glucose and fructose to total dissolved sugars is less than 0.005,0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.20, 0.25,or 0.30 weight/weight. In some embodiments, the xylose-enriched stream1837-A is a sugar mixture with a high xylose to total sugars ratio, alow oligosaccharides to total dissolved sugars ratio, and a low glucoseand fructose contents.

In some sugar mixtures 1837-A, the arabinose to total dissolved sugarsratio is less than 0.001, 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, 0.03,0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.20 or 0.30 weight/weight. Insome sugar mixtures 1837-A, the galactose to total dissolved sugarsratio is less than 0.0005, 0.001, 0.002, 0.003, 0.004, 0.005, 0.01,0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, or 0.10 weight/weight.In some sugar mixtures 1837-A, the mannose to total dissolved sugarsratio is less than 0.001, 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, 0.03,0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.20 or 0.30 weight/weight. Insome sugar mixtures 1837-A, the fructose to total dissolved sugars ratiois less than 0.001, 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, 0.03, 0.04,0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.20 or 0.30 weight/weight.

The sugar mixture 1837-A includes a very low concentration of impurities(e.g., furfurals and phenols). In some sugar mixtures 1837-A, the sugarmixture has furfurals in an amount up to 0.1%, 0.05%, 0.04%, 0.03%,0.04%, 0.01%, 0.075%, 0.005%, 0.004%, 0.002%, or 0.001% weight/weight.In some sugar mixtures 1837-A, the sugar mixture has phenols in anamount up to 500 ppm, 400 ppm, 300 ppm, 200 ppm, 100 ppm, 60 ppm, 50ppm, 40 ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm, 1 ppm, 0.1 ppm, 0.05 ppm,0.02 ppm, or 0.01 ppm. The sugar mixture is further characterized by atrace amount of hexanol, e.g., 0.01-0.02%, 0.02-0.05%, 0.05-0.1%,0.1%-0.2%, 0.2-0.5%, 0.5-1%, or less than 1, 0.5, 0.2, 0.1, 0.05, 0.02,0.01, 0.005, 0.002, 0.001%, weight/weight hexanol.

The xylose-removed hemicellulose sugar mixture 1837-B is characterizedby one or more, two or more, three or more, four or more, five or more,six or more, seven or more, eight or more, nine or more, ten or morecharacteristics including (i) oligosaccharides in a ratio to totaldissolved sugars >0.15 weight/weight; (ii) the sum of glucose andfructose in a ratio to total dissolved sugars >0.10 weight/weight; (iii)arabinose in a ratio to total dissolved sugars >0.02 weight/weight; (iv)galactose in a ratio to total dissolved sugars >0.02 weight/weight; (v)xylose in a ratio to total dissolved sugars <0.20; (vi) mannose in aratio to total dissolved sugars >0.01; (vii) fructose in a ratio tototal dissolved sugars <0.05; (viii) furfurals in an amount up to 0.01%weight/weight; (ix) phenols in an amount up to 500 ppm; and (x) a traceamount of hexanol. For example, the sugar mixture can be a mixturecharacterized by a high oligosaccharides to total dissolved sugarsratio, and a high glucose/fructose to total dissolved sugars ratio. Insome embodiments, the sugar mixture 1837-B is a mixture characterized bya high oligosaccharides to total dissolved sugars ratio, a highglucose/fructose to total dissolved sugars ratio, and a low impuritycontents (e.g., low furfurals and phenols). In some embodiments, thesugar mixture is a mixture characterized by a high oligosaccharides tototal dissolved sugars ratio, a high glucose/fructose to total dissolvedsugars ratio, a low impurity contents (e.g., low furfurals and phenols),and a trace amount of hexanol. In some embodiments, the sugar mixture isa mixture characterized by a high xylose concentration, a higholigosaccharides to total dissolved sugars ratio, a high ratio of thesum of glucose and fructose to total dissolved sugars ratio, and a lowimpurity contents (e.g., low furfurals and phenols).

In some embodiments, the xylose-removed hemicellulose sugar mixture1837-B is a sugar mixture characterized by a high oligosaccharides tototal dissolved sugars ratio. In some sugar mixtures, theoligosaccharides to total dissolved sugars ratio is larger than 0.15,0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, or 0.65 weight/weight.In some embodiments, the xylose-removed hemicellulose sugar mixture1837-B is a sugar mixture with a high glucose/fructose content. In somesugar mixtures, the ratio of the sum of glucose and fructose to totaldissolved sugars is larger than 0.05, 0.10, 0.13, 0.15, 0.20, 0.25,0.30, 0.35, 0.40, 0.45, 0.50, or 0.55 weight/weight. In someembodiments, the xylose-depleted liquor is a sugar mixture with a higholigosaccharides to total dissolved sugars ratio, and a high glucose andfructose contents.

In some sugar mixtures 1837-B, the arabinose to total dissolved sugarsratio is larger than 0.02, 0.03, 0.04, 0.05, 0.06, 0.08, 0.10, 0.12,0.20, or 0.30 weight/weight. In some sugar mixtures 1837-B, thegalactose to total dissolved sugars ratio is larger than 0.02, 0.03,0.04, 0.05, 0.06, 0.08, 0.10, 0.12, 0.20, or 0.30 weight/weight. In somesugar mixtures 1837-B, the xylose to total dissolved sugars ratio isless than 0.30, 0.20, 0.18, 0.17, 0.16, 0.15, 0.12, 0.10, or 0.05weight/weight. In some sugar mixtures 1837-B, the mannose to totaldissolved sugars ratio is larger than 0.005, 0.006, 0.007, 0.008, 0.010,0.015, or 0.020 weight/weight. In some sugar mixtures 1837-B, thefructose to total dissolved sugars ratio is less than 0.005, 0.01, 0.02,0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, or 0.20 weight/weight.

The sugar mixture 1837-B includes a very low concentration of impurities(e.g., furfurals and phenols). In some resulting stream, the sugarmixture has furfurals in an amount up to 0.1%, 0.05%, 0.04%, 0.03%,0.04%, 0.01%, 0.075%, 0.005%, 0.004%, 0.002%, or 0.001% weight/weight.In sugar mixtures 1837-B, the sugar mixture has phenols in an amount upto 500 ppm, 400 ppm, 300 ppm, 200 ppm, 100 ppm, 60 ppm, 50 ppm, 40 ppm,30 ppm, 20 ppm, 10 ppm, 5 ppm, 1 ppm, 0.1 ppm, 0.05 ppm, 0.02 ppm, or0.01 ppm. The sugar mixture is further characterized by a trace amountof hexanol, e.g., 0.01-0.02%, 0.02-0.05%, 0.05-0.1%, 0.1%-0.2%,0.2-0.5%, 0.5-1%, or less than 1, 0.5, 0.2, 0.1, 0.05, 0.02, 0.01,0.005, 0.002, 0.001%, weight/weight hexanol.

6. Sugar Crystallization

This exemplary description is related to the processes denoted in FIGS.4, 5 and 6 by the number X08, where X is 4, 5, or 6 respectively(process 1841 in FIG. 18). Pure xylose is known to crystallize out ofsupersaturated mixed sugar solutions. To achieve that, the sugarsolution stream resulting from the sugar refining of X07 is concentratedby evaporation X10, and fractionated by chromatographic separation atX09 to produce a xylose-enriched stream (corresponding to 1837-A in FIG.18) having more than 75, 78, 80, 82, 84, 85, 86, 88, 90% xylose, and axylose-removed hemicellulose sugar mixture (corresponding to 1837-B inFIG. 18). The xylose-enriched stream (corresponding to 1837-A in FIG.18) coming out of fractionation X09 is fed into a crystallization moduleX08 (process 1841 in FIG. 18) to produce xylose crystals.

In some methods, the xylose-enriched stream 1837-A is optionally furtherevaporated before it is fed into a crystallization module 1841 toproduce xylose crystals. The crystals can be harvested from the motherliquor by any suitable means, e.g., centrifugation. Depending on thecrystallization technique, the crystals can be washed with theappropriate solution, e.g., an aqueous solution or solvent. The crystalscan be either dried or re-dissolved in water to make xylose syrup.Typically a yield of 45-60% of the potential xylose can be crystallizedin a 20-35, preferably 24-28 hour cycle.

After crystallization, the mother liquor hemicellulose sugar mixture1843 can be recycled back to the fractionation step as it contains avery high content of xylose, e.g., >57% xylose, >65% and moretypically >75% xylose. Alternatively, the mother liquor hemicellulosesugar mixture 1843 can be sent to anaerobic digestion to harvest theenergy attainable from this fraction.

In some embodiments, the mother liquor hemicellulose sugar mixture 1843is a sugar mixture characterized by a high xylose concentration. In somesugar mixtures, the sugar mixture has more than 65, 67, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, or 85% weight/weight xylose.

Sugar solution stream originating from some hardwood and specificgrasses such as bagasse can contain at least 60% xylose and moretypically 60-80% or 66-73% weight/weight xylose. Xylose can be used as araw material for bacterial and chemical production of furfural andtetrahydrofuran. Xylose can also be used as the starting material forpreparing xylitol, a low calorie alternative sweetener that hasbeneficial properties for dental care and diabetes management, and hasbeen shown to contribute to clearing ear and upper respiratory tractinfections. Given these beneficial properties, xylitol is incorporatedin food and beverages, toothpastes and mouth wash products, chewing gumsand confectionary products. World xylitol market is limited due to itshigh price compared to other non-reducing polyol sugars (ca. sorbitol,mannitol). The method of the present invention provides a cost-effectiveproduction method for xylose and xylitol.

The mother liquor hemicellulose sugar mixture 1843 is characterized byone or more, two or more, three or more, four or more, five or more, sixor more, seven or more, eight or more, nine or more, ten or morecharacteristics including (i) oligosaccharides in a ratio to totaldissolved sugars <0.15 weight/weight; (ii) xylose in a ratio to totaldissolved sugars >0.40 weight/weight; (iii) arabinose in a ratio tototal dissolved sugars <0.15 weight/weight; (iv) galactose in a ratio tototal dissolved sugars <0.06 weight/weight; (v) the sum of glucose andfructose in a ratio to total dissolved sugars <0.20 weight/weight; (vi)mannose in a ratio to total dissolved sugars <0.03; (vii) fructose in aratio to total dissolved sugars <0.04; (viii) furfurals in an amount upto 0.01% weight/weight; (ix) phenols in an amount up to 500 ppm; and (x)a trace amount of hexanol. For example, the sugar mixture 1843 is amixture characterized a low oligosaccharides to total dissolved sugarsratio and a high xylose to total dissolved sugars ratio. In someembodiments, the sugar mixture 1843 is a mixture characterized by a lowoligosaccharides to total dissolved sugars ratio, a high xylose to totaldissolved sugars ratio, and a low impurity contents (e.g., low furfuralsand phenols). In some embodiments, the sugar mixture 1843 is a mixturecharacterized by a low oligosaccharides to total dissolved sugars ratio,a high xylose to total dissolved sugars ratio, a low impurity contents(e.g., low furfurals and phenols), and a trace amount of hexanol. Insome embodiments, the sugar mixture 1843 is a mixture characterized by alow oligosaccharides to total dissolved sugars ratio, a high xylose tototal dissolved sugars ratio, a low ratio of the sum of glucose andfructose to total dissolved sugars ratio, a low impurity contents (e.g.,low furfurals and phenols), and a trace amount of hexanol.

In some embodiments, the mother liquor hemicellulose sugar mixture 1843is a sugar mixture characterized by a high xylose to total dissolvedsugars ratio. In some sugar mixtures, the xylose to total dissolvedsugars ratio is larger than 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65,0.70, 0.75, 0.80, or 0.85 weight/weight. In some embodiments, the motherliquor hemicellulose sugar mixture 1843 is a sugar mixture characterizedby a low oligosaccharides to total dissolved sugars ratio. In some sugarmixtures, the oligosaccharides to total dissolved sugars ratio is lessthan 0.005, 0.007, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09,0.10, 0.20, 0.30, or 0.35 weight/weight. In some embodiments, the motherliquor hemicellulose sugar mixture 1843 is a sugar mixture with a lowglucose/fructose content. In some sugar mixtures, the ratio of the sumof glucose and fructose to total dissolved sugars is less than 0.01,0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.20, 0.25, 0.30,or 0.35 weight/weight. In some embodiments, the mother liquorhemicellulose sugar mixture 1843 is a sugar mixture with a high xyloseto total sugars ratio, a low oligosaccharides to total dissolved sugarsratio, and a low glucose and fructose contents.

In some sugar mixtures 1843, the arabinose to total dissolved sugarsratio is less than 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, 0.03, 0.04,0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.15, 0.20, 0.25, 0.30 or 0.35weight/weight. In some sugar mixtures 1843, the galactose to totaldissolved sugars ratio is less than 0.001, 0.002, 0.003, 0.004, 0.005,0.010, 0.015, 0.020, 0.025, 0.030, 0.035, 0.040, 0.05, 0.06, 0.065,0.07, 0.08, 0.09, or 0.10 weight/weight. In some sugar mixtures 1843,the mannose to total dissolved sugars ratio is less than 0.001, 0.002,0.003, 0.004, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08,0.09, 0.10, 0.20 or 0.30 weight/weight. In some sugar mixtures 1843, thefructose to total dissolved sugars ratio is less than 0.001, 0.002,0.003, 0.004, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08,0.09, 0.10, 0.20 or 0.30 weight/weight.

The sugar mixture 1843 includes a very low concentration of impurities(e.g., furfurals and phenols). In some sugar mixtures 1843, the sugarmixture has furfurals in an amount up to 0.1%, 0.05%, 0.04%, 0.03%,0.04%, 0.01%, 0.075%, 0.005%, 0.004%, 0.002%, or 0.001% weight/weight.In some sugar mixtures 1843, the sugar mixture has phenols in an amountup to 500 ppm, 400 ppm, 300 ppm, 200 ppm, 100 ppm, 60 ppm, 50 ppm, 40ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm, 1 ppm, 0.1 ppm, 0.05 ppm, 0.02 ppm,or 0.01 ppm. The sugar mixture is further characterized by a traceamount of hexanol, e.g., 0.01-0.02%, 0.02-0.05%, 0.05-0.1%, 0.1%-0.2%,0.2-0.5%, 0.5-1%, or less than 1, 0.5, 0.2, 0.1, 0.05, 0.02, 0.01,0.005, 0.002, 0.001%, weight/weight hexanol.

7. Hemicellulose Sugar Product

This section relates to the use of the mixed sugars streams produced atthe sugar refining step X07, or fractionated from the xylose-enrichstream at step X09, wherein X is 4, 5 or 6 in FIGS. 4, 5, and 6,respectively. This high purity mixed sugar product can be used in afermentation process. Such fermentation process may employ amicroorganism or genetically modified microorganism (GMO) from thegenera Clostridium, Escherichia (e.g., Escherichia coli), Salmonella,Zymomonas, Rhodococcus, Pseudomonas, Bacillus, Enterococcus,Alcaligenes, Lactobacillus, Klebsiella, Paenibacillus, Corynebacterium,Brevibacterium, Pichia, Candida, Hansenula and Saccharomyces. Hosts thatmay be particularly of interest include Oligotropha carboxidovorans,Escherichia coli, Bacillus licheniformis, Paenibacillus macerans,Rhodococcus erythropolis, Pseudomonas putida, Lactobacillus plantarum,Enterococcus faecium, Cupriavidus necator, Enterococcus gallinarium,Enterococcus faecalis, Bacillus subtilis and Saccharomyces cerevisiae.Also, any of the known strains of these species may be utilized as astarting microorganism. Optionally, the microorganism may be anactinomycete selected from Streptomyces coelicolor, Streptomyceslividans, Streptomyces hygroscopicus, or Saccharopolyspora erytraea. Invarious exemplary embodiments, the microorganism can be a cubacteriumselected from Pseudomonas fluorescens, Pseudomonas aeruginosa, Bacillussubtilis or Bacillus cereus. In some examples, the microorganism orgenetically modified microorganism is a gram-negative bacterium.

Conversion product made through fermentation can be, for example, analcohol, carboxylic acid, amino acid, monomer for the polymer industryor protein. A particular example is lactic acid, which is the monomerbuilding polylactic acid, a polymer with numerous uses.

The conversion product can be processed to produce a consumer productselected from the group consisting of a detergent, a polyethylene-basedproduct, a polypropylene-based product, a polyolefin-based product, apolylactic acid (polylactide)-based product, apolyhydroxyalkanoate-based product and a polyacrylic-based product. Thedetergent can include a sugar-based surfactant, a fatty acid-basedsurfactant, a fatty alcohol-based surfactant or a cell-culture derivedenzyme.

The polyacrylic-based product can be a plastic, a floor polish, acarpet, a paint, a coating, an adhesive, a dispersion, a flocculant, anelastomer, an acrylic glass, an absorbent article, an incontinence pad,a sanitary napkin, a feminine hygiene product and a diaper. Thepolyolefin-based products can be a milk jug, a detergent bottle, amargarine tub, a garbage container, a plumbing pipe, an absorbentarticle, a diaper, a non-woven, an HDPE toy or an HDPE detergentpackaging. The polypropylene based product can be an absorbent article,a diaper or a non-woven. The polylactic acid based product can be apackaging of an agriculture product or of a dairy product, a plasticbottle, a biodegradable product or a disposable. Thepolyhydroxyalkanoate based products can be packaging of an agricultureproduct, a plastic bottle, a coated paper, a molded or extruded article,a feminine hygiene product, a tampon applicator, an absorbent article, adisposable non-woven or wipe, a medical surgical garment, an adhesive,an elastomer, a film, a coating, an aqueous dispersant, a fiber, anintermediate of a pharmaceutical or a binder. The conversion product canbe ethanol, butanol, isobutanol, a fatty acid, a fatty acid ester, afatty alcohol or biodiesel.

Xylose can be reacted with chlorambucil to obtain benzenebutanoic acid,4-[bis(2-chloroethyl)amino]-, 2-β-D-xylopyranosylhydrazide, aglycosylated chlorambucil analog which is useful as antitumor and/oranti-metastatic agent. Xylose may be reacted with phenethyl bromide and1-bromo-3,3-dimethoxypropane to obtain (2S,3S,4S)-2H-Pyrrole,3,4-dihydro-3,4-bis(phenyl-methoxy)-2-[(phenylmethoxy)methyl]-, 1-oxide,used as α-glucosidase inhibitor for preventing and/or treating diabetesmellitus, hyperlipidemia, neoplasm, and viral infection.

The sugar mix product can be converted to fuel products, for example, anisobutene condensation product, jet fuel, gasoline, gasohol, dieselfuel, drop-in fuel, diesel fuel additive or a precursor thereof. Thisconversion may be done through fermentation or by catalyzed chemicalconversion. The gasohol may be ethanol-enriched gasoline and/orbutanol-enriched gasoline.

Consumer products, precursor of a consumer product, or ingredient of aconsumer product can be made from the conversion product or include atleast one conversion product such as, for example, a carboxylic or fattyacid, a dicarboxylic acid, a hydroxylcarboxylic acid, ahydroxyldicarboxylic acid, a hydroxyl-fatty acid, methylglyoxal, mono-,di-, or poly-alcohol, an alkane, an alkene, an aromatic, an aldehyde, aketone, an ester, a biopolymer, a protein, a peptide, an amino acid, avitamin, an antibiotics and a pharmaceutical. For example, the productmay be ethanol-enriched gasoline, jet fuel, or biodiesel.

The consumer product may have a ratio of carbon-14 to carbon-12 of about2.0×10⁻¹³ or greater. The consumer product can include an ingredient ofa consumer product as described above and an additional ingredientproduced from a raw material other than lignocellulosic material. Insome cases, ingredient and the additional ingredient produced from a rawmaterial other than lignocellulosic material are essentially of the samechemical composition. The consumer product can include a marker moleculeat a concentration of at least 100 ppb. The marker molecule can be, forexample, hexanol, 1-ethyl hexanol, furfural or hydroxymethylfurfural,products of furfural or hydroxymethylfurfural condensation, colorcompounds derived from sugar caramelization, levulinic acid, aceticacid, methanol, galacturonic acid or glycerol.

IV. Cellulose Hydrolysis

Once hemicellulose sugars are extracted, lignocellulosic remainderstream 1700-B can be subject to cellulose hydrolysis 1720 to obtain anacidic hydrolysate stream 1720-A and acidic lignin stream 1720-B (see,FIG. 17). Preferably, prior to the cellulose hydrolysis, biomass ismilled or grinded to reduce particle size (see, e.g., FIG. 3 and FIG. 6,number 310 and 610). Once hemicellulose sugar is extracted, it is mucheasier to mill or grind the lignocellulosic remainder. Therefore, it ispreferred to mill or grind biomass at this stage as it consumes lessenergy.

Compared to ungrounded particles such as chips, ground particles can besuspended in the hydrolysis liquid, and can be circulated from containerto container. Ground particles from different lignocellulosic biomassmaterials can be processed by the same set of equipments using similaror same operating parameters. Reduced particle size greatly acceleratesthe downstream cellulose hydrolysis process. Preferably, thelignocellulosic biomass is grinded such that the average size of theparticles is in the range of 100-10,000 micron, preferably 400-5,000,e.g., 100-400, 400-1,000, 1,000-3,000, 3,000-5,000, or 5,000-10,000microns. Preferably, the lignocellulosic biomass is grinded such thatthe average size of the particles is less than 10,000, 9,000, 8,000,7,000, 6,000, 5,000, 4,000, 3,000, 1,000, or 400.

Any hydrolysis methods and systems can be used for cellulose hydrolysis,including enzymatic means and chemical methods. For example, simulatedmoving bed systems can be used for cellulose hydrolysis as disclosed inWO2012061085 (incorporated herein by reference for all purposes). In oneembodiment, the present invention contemplates a method of extractingcellulose sugars using the stirred tank hydrolysis system (see, FIG.8A). This counter current system is advantageous for acid hydrolysis ofcellulose sugars. When multiple tanks are used, the system enablesseparate temperature control for each individual tank. The system can beadapted for various lignocellulosic biomass materials.

As exemplified in FIG. 8A, lignocellulosic remainder stream 1700-B atmoisture content of 5 to 85% weight/weight is milled or grinded toparticle size of 400-5000 micron (preferably ˜1400 micron) by anyindustrial mill including hammer mill and pin mill. If moisture contentis higher than 15%, the ground lignocellulosic remainder is dried tohave moisture ≦15%. The hydrolysis system includes a number of n stirredtanks (e.g., n=1-9, preferably 4) connected in series as depicted inFIG. 8A. The aqueous liquid in the tank, containing acid, dissolvedsugar and suspended biomass is recycled by a high pressure high flowrate pump causing stirring of the solution in each tank. The flow lineis also fitted with a solid/liquid separation device (e.g., a filter, amembrane, or a hydrocylone) that allows at least some of the liquid anddissolved molecules, i.e. acid and sugars, to permeate thereby producinga permeate (or filtrate) stream. At least some of the feed liquid isretained by the solid/liquid separation device to produce retentatestream thus producing stirring of the liquid in the reactor. Superazeotropic HCl solution with acid concentration of at least 41% is fedinto tank n. The permeate of the separation unit of tank n is fed intoreactor n-1 while at least part of the retentate is recycled back intotank n. The permeate of tank n-1 is fed into tank n-2 while theretentate is recycled back into tank n-1 and so on. The permeate exitingtank 1 of the series is the acidic hydrolysate stream 1720-A. The solidsconcentration in each stirred tank reactor can be maintained between3-15%, 3-5%, 5-10%, or 10-15% weight/weight. Overall, the biomass isretained in the system over 10 to 48 hours. The temperature of eachreactor is controlled separately at the range 5 to 40° C.

In some embodiments, the ground lignocellulosic remainder stream 1700-Bis added to the first stage of a series of stirred tank reactors (e.g.,1 to 9 reactors, preferably 4 reactors). The slurry is mixed thoughagitation or recirculation of the liquor inside the reactors. At leastsome of the retentate of tank 1 is fed into tank 2; at least some of theretentate of tank 2 is fed into tank 3 and so on. Eventually acidiclignin stream 1720-B exits tank n to the lignin wash system.

In some embodiments, concentrated hydrochloric acid (>35%, 36%, 37%,38%, 39%, 40%, 41%, or preferably 42%) is added into the last reactor inthe series, and less concentrated hydrochloric acid (˜25%, 26%, 27%,28%, 29%, 30%, or preferably 31%,) exits from the first reactor in theseries.

In some embodiments, hydrolyzed sugars exit from the first reactor inthe series. The acidic hydrolysate stream 1720-A containing the acid andcellulose sugars is transferred from the last reactor to the second tothe last reactor and so on until the hydrolysate leaves the firstreactor for additional purification. In an exemplary reactor system, thehydrolysate leaving the first reactor has between 8-16% sugars andhydrochloric acid. In some embodiments, the acidic hydrolysate stream1720-A can contain more than 8%, 9%, 10%, 11%, 12%, 13%, 14%, dissolvedsugars. In some embodiments, the acidic hydrolysate stream 1720-A cancontain more than 22%, 24%, 26%, 28%, 30%, 32% 34%, or 36% HCl. In someembodiments, the acidic hydrolysate stream 1720-A can contain less than32%, 30%, 28%, 26%, 24%, 22%, or 20% HCl.

The temperature in all the reactors is maintained in the range of 5-80°C., e.g., 15-60° C., preferably 10-40° C. Total retention time of thebiomass in all reactors can range from 1 to 5 days, e.g., 1 to 3 days,preferably 10 to 48 hours.

Preferably, when multiple stirred tank reactors are used, at least aportion of the aqueous acid hydrolysate stream leaving an intermediatereactor (e.g., reactor 2 or 3) is mixed with the lignocellulosicremainder stream 1700-B before 1700-B stream is introduced into thefirst reactor. The 1700-B stream is pre-hydrolyzed by the aqueous acidhydrolysate stream from the intermediate reactor before it is contactedwith the strong acid in the first reactor. Preferably, thepre-hydrolysis mixture is heated to a temperature in the range of 15 to60° C., preferably 25 to 40° C., most preferably 40° C. for 5 minutes to1 day, preferably 15-20 minutes. In one example, eucalyptus ishydrolyzed using stirred tank reactors. Upon initial introduction of theeucalyptus wood into the acid, viscosity initially increases as a resultof fast dissolution of oligomers of cellulosic sugars, the highviscosity hinders the ability to pump and recirculate the aqueoussolution through the system; the short stirring of groundlignocellulosic remainder stream 1700-B with intermediate reactorhydrolysate at elevated temperature accelerates further hydrolysis ofthe dissolved oligomers to monomer, accompanied with decrease inviscosity. In another example, eucalyptus is first contacted with acidsolution coming out of stage 2 (i.e. concentration ˜33%) at 35-50° C.for 15-20 minutes. The pre-hydrolyzed eucalyptus can be fed into thesystem much faster and is further hydrolyzed in the stirred tankreactors.

Stirred tank reactors can be used for various materials includinghardwood, softwood, and bagasse. Exemplary results using a 4-reactorstirred tank system is provided in FIG. 8B.

After the cellulose hydrolysis, the remaining residues in thelignocellulosic biomass form acidic lignin stream 1720-B. Acidic ligninstream 1720-B can be further processed and refined to produce novellignin compositions as described in more detail herein. The acidichydrolysate stream 1720-A produced by cellulose hydrolysis is furtherrefined as described below.

V. Cellulose Sugar Refining

The present invention provides a method for refining sugars.Specifically, the present method efficiently refines sugars from theacidic hydrolysate stream 1720-A containing a mineral acid (e.g., HCl orH₂SO₄). An output cellulose sugar composition according to embodimentsdisclosed herein has a high content of monomeric sugars.

An exemplary method of cellulose sugar refining according to someembodiments of the present invention is provided in FIG. 19 (process1900). The acidic hydrolysate stream 1720-A can be subject to S1 solventextraction 1921, during which the acidic hydrolysate stream 1720-A iscontacted with a S1 solvent extractant, and acids are extracted from the1720-A stream into the S1 solvent extractant. The resulting mixture isseparated into a first stream 1921-A (organic stream) containing theacid and the S1 solvent extractant and a second stream 1921-B (aqueousstream) containing cellulose sugars.

Optionally, S1 solvent extraction 1921 can be conducted in multiplesteps, e.g., two or more steps. Preferably, S1 solvent extraction 1921is conducted in two steps: 1921-I and 1921-II. In some methods, duringextraction 1921-I, the acid concentration in the acidic hydrolysatestream 1720-A is reduced to less than 15%, less than 14% less than 13%,less than 12%, or less, resulting in a partially deacidifiedhydrolysate. In some methods, the partially deacidified hydrolysate isevaporated to remove water, resulting in increased sugar and acidconcentrations (e.g., an acid concentration between 13% and 14%weight/weight). Preferably, the concentrated partially deacidifiedhydrolysate is extracted with S1 solvent again during extraction1921-II, resulting in a sugar stream containing less than 5% less than4% less than 3%, preferably between 2 and 3% acid or less.

In some methods, stream 1921-A is washed to recover sugars by extractionwith a HCl stream at 20-25%. In some methods, extraction 1921-A,extraction 1921-B, contacting the first stream 1921-A and backextraction 1950 are conducted at 40 to 60° C., at 45 to 55° C.,preferably at 50° C.

In some methods, the second stream 1921-B is diluted with oligomericsugars 1931 from downstream fractionation process 1930 and optionallywith additional aqueous streams. When oligomeric sugars 1931 is combinedwith the second stream 1921-B, the oligomeric sugars is hydrolyzed bythe residual acids in the second stream 1921-B (the “secondaryhydrolysis” process 1929 in FIG. 19).

The second stream 1921-B can be optionally contacted with a strong acidcation exchanger 1922 to convert salts to their respective acids. Thesugar stream is then extracted with an amine extractant to removemineral acid(s), organic acids, furfurals, acid soluble lignins (process1923 in FIG. 19), during which the sugar stream is contacted with anamine extractant comprising and amine and a diluent. The resultingmixture is separated into a third stream 1923-A (organic stream)containing the acid and the amine extractant and a fourth stream 1923-B(aqueous stream) containing cellulose sugars. In some methods,contacting with the amine extractant is conducted at 50-80° C., at55-70° C., preferably at 70° C.

The fourth stream 1923-B is then purified by evaporation to removeresidual diluent which is dissolved in the aqueous phase followed by ionexchange means 1924, including a strong acid cation exchanger 1925 toremove amines and optionally followed by a weak base anion exchanger1926. The amine-removed and neutralized hydrolysate 1924-A can beoptionally evaporated (process 1927 in FIG. 19) to form a cellulosesugar stream 1928, which can be further fractionated to obtain highmonomeric C6 sugars such as glucose (process 1930 in FIG. 19).Fractionation separates a monomeric sugars stream 1932 from anoligomeric sugar stream 1931.

The monomeric sugar stream 1932 can be optionally evaporated to higherconcentration (process 1933) followed by neutralization using an ionexchanger (process 1934). The neutralized monomeric sugar stream is thenoptionally evaporated again (process 1935 in FIG. 19) to produce acellulose sugar mixture 1936.

The acids in the sugar depleted stream 1921-A can be recovered (process1940 in FIG. 19). At least a portion of the solvent can be purified andrecycled back to S1 solvent extraction 1921. A portion of the S1 solventcan be further purified using a lime solution (e.g. calcium oxide,calcium hydroxide, calcium carbonate, or a combination thereof) and thepurified solvent can be recycled back to the S1 solvent extraction 1921.

The third stream 1923-A can be back-extracted with an aqueous solutioncontaining a base (process 1950 in FIG. 19). The back-extracted aminecan be recycled back to amine extraction 1923. At least a portion of thesolvent can be purified using a lime solution ((e.g. calcium oxide,calcium hydroxide, calcium carbonate, or a combination thereof))(process 1960 in FIG. 19) and the purified solvent can be recycled backto amine extraction 1923.

A more detailed description of these exemplary cellulose sugar refiningembodiments is provided below.

1. Pre-Evaporation

After the cellulose hydrolysis and prior to S1 solvent extraction 1921,the acidic hydrolysate stream 1720-A can be optionally evaporated(process 1910 in FIG. 19) to concentrate the sugars and remove themineral acid (e.g., HCl). For example, the HCl concentration in thestream (e.g., ˜33%) is higher than its azeotrope (˜22%), the sugarstream can be first evaporated to remove the acid gas to azeotrope. The1720-A stream is then evaporated to the sugar concentration target atthe azeotrope which allows multiple effect concentration. An evaporatedsugar solution having about 30% dry solid contents can be obtained bythis process.

The evaporated sugar stream (e.g., having azeotropic HCl) can beextracted with an extractant (process 1921 in FIG. 19) as describedbelow. Alternatively, the acidic hydrolysate stream 1720-A (e.g., havingsuper-azeotropic HCl, e.g., 22-33% or more HCl) can be directlyextracted with an extractant without the evaporation step.

2. Extraction

Preferred extractant is an extractant containing an S1 solvent (process1921 in FIG. 19). The S1 solvent suitable for use in the extraction is asolvent that has a boiling point at 1 atm between 100° C. and 200° C.and forms a heterogeneous azeotrope with water. In some S1 solvents, theheterogeneous azeotrope has a boiling point at 1 atm of less than 100°C. For example, the S1 solvent can be a solvent containing an alcohol orkerosene. Examples of alcohols suitable for making a S1 solvent includebutanol, isobutanol, hexanol, octanol, decanol, dodecanol, tetradecanol,pentadecanol, hexadecanol, octadecanol, eicosanol, docosanol,tetracosanol, and triacontanol. Preferably, the S1 solvent is a longchain alcohol (e.g. C6, C8, C10, C12, C14, C16 alcohol), or kerosene.More preferably, the S1 solvent comprises n-hexanol or 2-ethyl-hexanolor mixtures thereof. Most preferably, the S1 solvent comprisesn-hexanol. In some embodiments, the S1 solvent consists essentially of,or consists of, n-hexanol.

Optionally, the S1 solvent comprises one or more additional components.In some methods, the S1 solvent comprises one or more ketones, one ormore aldehydes having at least 5 carbon atoms, or another alcohol.

The extraction can be conducted in a countercurrent system. Optionally,the extraction can be conducted in multiple extraction columns, e.g.,two extraction columns. In the first column, the acid is extracted intothe extractant, leaving the acid concentration in the sugar stream lessthan azeotrope. The extractant leaving the column 1 can be optionallywashed with azeotropic acid water solution to recover any sugarsabsorbed in the extractant back to the water solution, which can berecycled in the hydrolysis. The sugar stream, now having less thanazeotropic acid concentration, is distilled. The sugar solution isre-concentrated, thereby achieving a higher acid concentration again.The re-concentrated sugar solution can be extracted with the extractantto remove residual acid. Overall the acid recovery can be more than97.5%.

A portion (e.g., 5-20, 10-15%) of the extractant washed with azeotropicacid water solution can be purified by various methods to remove acids,esters, soluble impurities such as furfurals and phenols. For example,the extractant can be purified by liming as disclosed in WO2012018740(incorporated herein by reference for all purposes). Preferably, theextractant is treated with lime at a 10% concentration. Preferably, thepurification is conducted using 5-10:1 lime to solvent ratio. Themixture is heated for, e.g., 1 hour at 85° C. The residual salts in themixture can be removed by separation means such as filtration orcentrifugation. The purified extractant is then recycled back to thewashed extractant.

3. Acid Recovery

The first stream 1921-A (acid-loaded S1 solvent extractant) can beback-extracted with water to recover the acids (process 1940 in FIG.19). After the acid recovery, an acid-free extractant (e.g., having lessthan 0.3-0.5% acid contents) is returned to extraction. An aqueoussolution containing about 15-20% acids is recovered, which can be usedin downstream processes, e.g., for washing lignin.

Optionally, prior to the acid recovery 1940, the first stream 1921-A canbe washed with an aqueous solution (preferably an acidic aqueoussolution) to recover any sugars in the stream. In some methods, thefirst stream 1921-A is washed with an azeotropic acid solution.Typically, after the washing, the amine extractant stream 1923-A hasless than 5%, 2%, 1%, 0.5%, 0.2%, 0.1%, 0.05% sugars.

The acid recovery can be carried out by any suitable methods.Preferably, the acid recovery is carried out by treating at least afraction of the back-extract in an evaporation module having at leastone low-pressure evaporator and at least one high-pressure evaporator.

In some methods, evaporation module can generate a super-azeotropicaqueous HCl solution and a sub-azeotropic aqueous HCl solution. Forexample, the low-pressure evaporator generates the super-azeotropicaqueous HCl solution and the high-pressure evaporator generates thesub-azeotropic aqueous HCl solution. In some embodiments, “highpressure” indicates super-atmospheric pressure, and “low pressure”indicates sub-atmospheric pressure. “Super-azeotropic” and“sub-azeotropic” indicates an HCl concentration relative to theazeotropic HCl concentration of a water/HCl mixture at ambienttemperature and ambient pressure. “Sub-azeotropic”

In some other methods, evaporation module generates a sub-azeotropicacid condensate, and super-azeotropic gaseous HCl. Optionally,low-pressure evaporator generates a sub-azeotropic acid condensatecontaining, e.g., up to 2%, 1%, 0.1% or 0.01% HCl on as is basis.Optionally, high-pressure evaporator generates super-azeotropic gaseousHCl. Preferably, low-pressure evaporator generates a sub-azeotropic acidcondensate and high-pressure evaporator generates super-azeotropicgaseous HCl.

The recycled HCl stream includes the gaseous HCl from the high-pressureevaporator (e.g. after absorption into an aqueous solution at anabsorber). The gaseous HCl can be mixed with azeotropic stream toproduce 42% acid for hydrolysis in a two-stage falling film absorbersystem.

The first stream 1921-A can be further treated with a lime suspension(e.g., a 5%, 10%, 15%, 20%, 25% weight/weight lime solution). Thesolvent to lime suspension ratio can be in the range 4-10, 4-5, 5-6,6-7, 7-8, 8-9, or 9-10. Treatment may be conducted in any suitabledevice, e.g., a thermostatic mixed tank. The solution can be heated forat least 1 hour at 80-90° C. Lime reacts with residual organic acids andesters of organic acids and adsorbs effectively organic impuritiespresent in the organic phase such as acid soluble lignin and furfurals,as visualized by change of color from dark to light. The contaminatedlime and impurities can be filtered or centrifuged to recover thepurified organic phase, which is washed with water and recycled back tothe S1 solvent extraction 1921. The aqueous stream may be diverted toother aqueous waste streams. Any solid cake that may be formed by thelime reaction may be used in the waste water treatment plant as aneutralization salt for residual acids from ion exchange regenerationsfor example.

4. Secondary Hydrolysis

The second stream 1921-B (acid-removed sugar stream) still contains aresidual amount of acids and oligomeric sugars, typically 2-3%. Thepresent method optionally provides a secondary hydrolysis step 1929 inwhich the residual acid in the sugar stream catalyzes the conversion ofoligomeric sugars to monomeric sugars.

Optionally, the second stream 1921-B is combined with a recoveredoligomeric sugar stream 1931 from downstream fractionation step andoptionally with additional aqueous streams.

The secondary hydrolysis can be conducted at a temperature greater than60° C., e.g., at 70° C.-130° C., 80° C.-120° C. or 90° C.-110° C.Preferably, the reaction is conducted at 120° C. The secondaryhydrolysis can be carried out for at least 10 minutes, between 20minutes and 6 hours, between 30 minutes and 4 hours or between 45minutes and 3 hours. Preferably, the reaction is conducted for about onehour.

Typically, secondary hydrolysis under these conditions increases theyield of monomeric sugars with minimal or no sugars degradation. Priorto secondary hydrolysis, the sugar stream typically contains 30-50%oligomeric sugars.

After secondary hydrolysis, the monomeric sugar content of the sugarstream as a fraction of total sugars can be is greater than 70%, 75,80%, 85%, or 90%. Preferably, the sugar stream after secondaryhydrolysis contains 86-89% or even more than 90% monomeric sugars as afraction of total sugars. Typically, degradation of monomeric sugarsduring the hydrolysis can be less than 1%, less than 0.2%, less than0.1% or less than 0.05%.

The second hydrolysis method can be applied more generally forhydrolyzing any oligomeric sugar stream. Preferably, the oligomericsugar stream (e.g., the second stream 1921-B, the recovered oligomericsugar stream 1931, or a mixture of the second stream 1921-B and therecovered oligomeric sugar stream 1931) is diluted before the secondhydrolysis (e.g., to a sugar concentration less than 5%, 6%, 7%, 8%, 9%,10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20% weight/weight). Insome second hydrolysis methods, the acid concentration in the sugarstream can be increased by adding an acid into the sugar stream. In somemethods, the acid concentration for carrying out the secondaryhydrolysis is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%,1.0%, 2.0%, or 5.0%. Preferably, the sugar stream contains 0.6-0.7% acidand 11% sugar.

5. Amine Extraction

Preferably, the sugar stream from the extraction and/or secondaryhydrolysis 1929 is deacidified to deplete acids in the stream.Optionally, the stream can first be contacted with a strong acid cationexchanger 1922 to convert salts into their respective acids. The sugarstream can then be subjected to extraction (e.g., counter-currently)with an extractant containing an amine base and a diluent to removemineral acid(s), organic acids, furfurals, acid soluble lignins (process1921 in FIG. 19). The amine extraction can be conducted under conditionsidentical or similar to those described above in connection withhemicellulose sugar purification.

The amine extractant can contain 10-90% or preferably 20-60%weight/weight of one or a plurality of amines having at least 20 carbonatoms. Such amine(s) can be primary, secondary, and tertiary amines.Examples of tertiary amines include tri-laurylamine (TLA; e.g. COGNISALAMINE 304 from Cognis Corporation; Tucson Ariz.; USA), tri-octylamine,tri-isooctylamine, tri-caprylylamine and tri-decylamine.

Diluents suitable for use in the amine extraction include an alcoholsuch as butanol, isobutanol, hexanol, octanol, decanol, dodecanol,tetradecanol, pentadecanol, hexadecanol, octadecanol, eicosanol,docosanol, tetracosanol, and triacontanol. Preferably, the diluent is along chain alcohol (e.g. C6, C8, C10, C12, C14, C16 alcohol), orkerosene. The diluent can have additional components. More preferably,the diluent comprises n-hexanol or 2-ethyl-hexanol. Most preferably, thediluent comprises n-hexanol. In some embodiments, the diluent consistsessentially of, or consists of, n-hexanol.

Optionally, the diluent contains one or more additional components. Insome methods, the diluent contains one or more ketones, one or morealdehydes having at least 5 carbon atoms, or another alcohol.

Preferably, the amine is tri-laurylamine and the diluent is hexanol.Preferably, the amine extraction solution contains tri-laurylamine andhexanol in a ratio of 3:7.

The amine extraction can be conducted at any temperature at which theamine is soluble, preferably at 50-70° C. Optionally, more than oneextraction steps (e.g., 2, 3, or 4 steps) can be used. The ratio of theamine extractant stream (organic phase) to the hemicellulose sugarstream1800-A (aqueous phase) can be 0.5-5:1, 1-2.5:1, or preferably,1.5-3.0:1.

The amine extraction method can be applied more generally for refiningor purifying any sugar stream (e.g., hemicellulose sugar stream,cellulose sugar stream, a mixed sugar stream), particularly a mildlyacidic sugar stream (e.g., containing 1-5%, 0.1-1%, 1-2%, 2-3%, 3-4%,5-6%, weight/weight acid). The amine extraction method according to someembodiments of the invention is particularly useful for refining orpurifying a sugar stream containing impurities. Typical impurities in asugar stream include ash, acid soluble lignin, fatty acids, organicacids such as acetic acid and formic acid, methanol, proteins and/oramino acids, glycerol, sterols, rosin acid and waxy materials.Typically, using the amine extraction method, a sugar stream can bepurified to have less than 1%, 0.8%, 0.6%, 0.5%, 0.4%, 0.2%weight/weight or less impurities. In some methods, a sugar stream can bepurified to have less than 1%, 0.8%, 0.6%, 0.5%, 0.4%, 0.2%weight/weight or less acids.

8. Back Extraction

The third stream 1923-A (acid-loaded amine extractant) contains mineraland organic acid, as well as impurities extracted from biomass and sugardegradation products. The acids can be extracted from the third stream1923-A in a back extraction step 1950. The back extraction can beconducted under conditions identical or similar to those described abovein connection with hemicellulose sugar purification.

Optionally, prior to the back extraction 1950, the amine extractantstream 1923-A can be washed with an aqueous solution to recover anysugars in the stream. Typically, after the washing, the amine extractantstream 1923-A has less than 5%, 2%, 1%, 0.5%, 0.2%, 0.1%, 0.05% sugars.

9. Solvent Purification

The amine extractant stream, now neutralized after acid removal, can bewashed with water to remove salts remaining from the back extraction(process 1960 in FIG. 19). It is particularly preferred for certainblended extractants that can partially saturate with water (as is thecase of certain alcohols for example). The wash stream may be combinedwith the back extraction aqueous stream. The solvent purification 1960can be conducted under conditions identical or similar to thosedescribed above in connection with hemicellulose sugar purification.

The fraction diverted to purification step (process 1960 in FIG. 19) canbe treated with a lime suspension (e.g., a 5%, 10%, 15%, 20%, 25%weight/weight lime solution). The solvent to lime suspension ratio canbe in the range 4-10, 4-5, 5-6, 6-7, 7-8, 8-9, or 9-10. Treatment may beconducted in any suitable device, e.g., a thermostatic mixed tank. Thesolution can be heated for at least 1 hour at 80-90° C. Lime reacts withresidual organic acids and esters of organic acids and adsorbseffectively organic impurities present in the organic phase such as acidsoluble lignin and furfurals, as visualized by change of color from darkto light. The contaminated lime and impurities can be filtered orcentrifuged to recover the purified organic phase, which is washed withwater and recycled back to the amine extraction step (process 1923 inFIG. 19). The aqueous stream may be diverted to other aqueous wastestreams. Any solid cake that may be formed by the lime reaction may beused in the waste water treatment plant as a neutralization salt forresidual acids from ion exchange regenerations for example.

10. Sugar Purification

The sugars in the fourth stream 1923-B (de-acidified aqueous stream) canbe further purified. The sugar purification can be conducted underconditions identical or similar to those described above in connectionwith hemicellulose sugar purification.

For example, the fourth stream 1923-B can be contacted with a strongacid cation (SAC) exchanger 1925 to remove any residual metallic cationsand any residual amines, preferably followed by a weak base anion (WBA)exchanger 1926 to remove excess protons. The amine-removed andneutralized hydrolysate 1924-A can be pH adjusted and evaporated to25-65% and preferably 30-40% weight/weight dissolved sugars in anyconventional evaporator, e.g., a multiple effect evaporator or aMechanical Vapor Recompression (MVR) evaporator (process 1927 in FIG.19). Any residual solvent present in the aqueous phase can also beremoved by evaporation. For example, the solvent forms a heterogeneousazeotrope with water and can be separated and returned to the solventcycle. The concentrated sugar solution can be contacted with mixed bedresin system to remove any residual ions or color bodies. If desired,the now refined sugar solution may be concentrated further by andconventional evaporator or MVR.

The resulting cellulose sugar stream 1928 is a highly purified sugarsolution having a high monomeric ratio, e.g., about 85-95%monosaccharides out of the total dissolved sugars. The composition ofthe sugars depends on the composition of the starting biomass. Thepurity of the stream in all cases may be sufficient for fermentationprocesses and/or catalytic processes utilizing these sugars.

11. Sugar Fractionation

The cellulose sugar stream 1928 can be fractionated into a monomericsugar stream 1932 and an oligomeric sugar stream 1931 (process 1930 inFIG. 19). The cellulose sugar stream 1928 is a highly concentrated sugarstream. In some embodiments, the cellulose sugar stream 1928 can includeat least 40%, 45%, 50%, 51%, 52%, 53%, 54%, 55%, 56% or 58% orintermediate or greater concentrations of total sugars. Optionally, the1928 stream includes 40-75%, 45-60%, or 48-68% total sugarsweight/weight.

FIG. 16 is a simplified flow diagram of a method of cellulose sugarfractionation according to an exemplary embodiment of the invention. Asshown in process 1610 of FIG. 16, in some embodiments, the cellulosesugar stream 1928 is contacted with an anion exchanger prior to feeding1928 stream to a chromatographic resin in 1610. The anion exchanger canbe a weak base resin anion exchanger (WBA) or an anion an amine havingat least 20 carbon atoms.

The cellulose sugar stream 1928 (a mixture of cellulosic monomeric andoligomeric sugars) is then fed to a chromatographic resin. Optionally,sugars from secondary hydrolysis can be incorporated into the low acid(e.g., less than 0.5, 0.4, 0.3, 0.2 or 0.1% HCl) cellulose sugar stream1928.

Next, the chromatographic resin is then fed with an aqueous solution(optionally water) to produce an oligomer cut 1622 enriched inoligomeric sugars (compared to total sugars) relative to the mixture fedat 1610 and a monomer cut 1624 enriched in monomeric sugars (relative tototal sugars) relative to the mixture fed at 1610 (process 1620 in FIG.16). In some embodiments, monomer cut 1624 can have at least 80, 82, 84,86, 88, 90, 92, 94, 96 or 98% monomeric sugars out of total sugars (byweight). The aqueous solution fed to the chromatographic resin atprocess 1620 can be water from a previous evaporation step, or a streamof hemicellulose sugars from a pressure wash as described in co-pendingapplication PCT/US2012/064541 (incorporated herein by reference for allpurposes). In some embodiments, oligomer cut 1622 includes at least 5,10, 20, 30, 40, 50% or intermediate or greater percentages of the totalsugars recovered from the resin fed at 1610.

In some embodiments, oligomer cut 1622 can be further processed. Forexample, oligomer cut 1622 can be concentrated or evaporated. In someembodiments, oligomeric sugars in oligomer cut 1622 are hydrolyzed(process 1630), thereby increasing the ratio of monomers to oligomers inthe oligomer cut 1622. In some embodiments, hydrolyzing 1630 iscatalyzed by HCl at a concentration of not more than 1.5, 1.0, 0.8, 0.7,0.6, or 0.5%. In some embodiments, hydrolyzing 1630 is catalyzed by HClat a concentration of not more than 1.5, 1.2, 1, 0.9, 0.8, 0.7, 0.6,0.5% on a weight basis. In some embodiments, hydrolyzing 1630 iscatalyzed by HCl at a concentration of 0.3-1.5%; 0.4-1.2% or 0.45-0.9%weight/weight. In some embodiments, hydrolyzing 430 is performed at atemperature between 60 and 150° C.; between 70 and 140° C. or between 80and 130° C. A secondary hydrolysate 1632 enriched with monomeric sugars(relative to total sugars) can be produced by hydrolysis 1630 of atleast a portion of the oligomeric sugars in oligomer cut 1622. In someembodiments, sugars from secondary hydrolysate 1632 are used as aportion of the sugar mixture fed at 1610.

In some embodiments, secondary hydrolysate 1632 contains at least 70,72, 74, 76, 78, 80, 82, 84, 86, 88, 90, or 95% monomeric sugars relativeto the total sugar content. In some embodiments the total sugar contentof secondary hydrolysate 1632 is at least 86, 88, 90, 92, 94, 96, 98,99, 99.5, or 99.9% by weight of the sugar content.

The monomer cut 1624 forms a monomeric sugar stream 1932. The monomericsugar stream 1932 can be optionally evaporated to higher concentration(process 1933 in FIG. 19) before it is neutralized using an ionexchanger 1934. The neutralized monomeric sugar stream is thenoptionally evaporated again (processes 1935 in FIG. 19). The end productis a high concentration cellulose sugar mixture 1936.

The resulting high concentration cellulose sugar mixture 1936 ischaracterized by one or more, two or more, three or more, four or more,five or more, six or more characteristics including (i) monosaccharidesin a ratio to total dissolved sugars >0.85; (ii) glucose in a ratio tototal dissolved sugars in the range of 0.40-0.70; (iii) 1-200 ppmchloride; (iv) furfurals in an amount up to 0.01% weight/weight; (v)phenols in an amount up to 500 ppm; and (vi) a trace amount of hexanol.For example, the sugar mixture can be a mixture characterized by a highmonosaccharides (particularly glucose) to total dissolved sugars ratio.In some embodiments, the sugar mixture is characterized by a highmonosaccharides to total dissolved sugars ratio, a high glucose to totaldissolved sugars ratio, and 1-200 ppm chloride. In some embodiments, thesugar mixture is characterized by a high monosaccharides to totaldissolved sugars ratio, a high glucose to total dissolved sugars ratio,and a low impurity contents (e.g., low furfurals and phenols). In someembodiments, the sugar mixture is characterized by a highmonosaccharides to total dissolved sugars ratio, a high glucose to totaldissolved sugars ratio, a low impurity contents (e.g., low furfurals andphenols), and a trace amount of hexanol. In some embodiments, the sugarmixture is characterized by a high monosaccharides to total dissolvedsugars ratio, a high glucose to total dissolved sugars ratio, a lowimpurity contents (e.g., low furfurals and phenols), a trace amount ofhexanol, and 1-200 ppm chloride.

The high concentration C6 sugar mixture has a high monosaccharidecontent. In some embodiments, the monomeric sugar stream contains asugar mixture having monosaccharides to total dissolved sugars ratiolarger than 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, or 0.99. Insome embodiments, the monomeric sugar stream contains a sugar mixturehaving glucose to total dissolved sugars ratio in the range of0.40-0.70, 0.40-0.50, 0.50-0.60, 0.60-0.70, or 0.40-0.60. In someembodiments, the monomeric sugar stream contains a sugar mixture with ahigh monosaccharide content and a glucose to total dissolved sugarsratio in the range of 0.40-0.70.

In some embodiments, the monomeric sugar stream contains a sugar mixturehaving a xylose to total dissolved sugars ratio in the range of0.03-0.12, 0.05-0.10, 0.03-0.05, 0.05-0.075, 0.075-0.10, 0.12-0.12,0.12-0.15, or 0.15-0.20. In some embodiments, the monomeric sugar streamcontains a sugar mixture having an arabinose to total dissolved sugarsratio in the range of 0.005-0.015, 0.025-0.035, 0.005-0.010,0.010-0.015, 0.015-0.020, 0.020-0.025, 0.025-0.030, 0.030-0.035,0.035-0.040, 0.040-0.045, or 0.045-0.050. In some embodiments, themonomeric sugar stream contains a sugar mixture having a mannose tototal dissolved sugars ratio in the range of 0.14-0.18, 0.05-0.10,0.10-0.15, 0.15-0.20, 0.20-0.25, 0.25-0.30, or 0.30-0.40.

The sugar mixture has very low concentration of impurities such asfurfurals and phenols. In some resulting stream, the sugar mixture hasfurfurals in an amount up to 0.1%, 0.05%, 0.04%, 0.03%, 0.04%, 0.01%,0.075%, 0.005%, 0.004%, 0.002%, or 0.001% weight/weight. In someresulting stream, the sugar mixture has phenols in an amount up to 500ppm, 400 ppm, 300 ppm, 200 ppm, 100 ppm, 60 ppm, 50 ppm, 40 ppm, 30 ppm,20 ppm, 10 ppm, 5 ppm, 1 ppm, 0.1 ppm, 0.05 ppm, 0.02 ppm, or 0.01 ppm.The sugar mixture is further characterized by a trace amount of hexanol,e.g., 0.01-0.02%, 0.02-0.05%, 0.05-0.1%, 0.1%-0.2%, 0.2-0.5%, 0.5-1%, orless than 1, 0.5, 0.2, 0.1, 0.05, 0.02, 0.01, 0.005, 0.002, 0.001%,weight/weight hexanol. In addition, the sugar mixture is characterizedby a trace amount of chloride, e.g., 1-10, 10-20, 20-30, 30-40, 40-50,50-100, 100-150, 150-200, 10-100, or 10-50 ppm chloride.

VI. Lignin Processing

After the cellulose hydrolysis, the remaining residues in thelignocellulosic biomass are mostly lignins. The present inventionprovides methods of making novel lignin compositions using a uniqueprocessing and refining system. An exemplary method of lignin processingaccording to some embodiments of the present invention is provided inFIG. 20 (process 2000).

1. Lignin Washing

The lignin washing process 2020 is designed to remove free sugars andhydrochloric acid, which remain with acidic lignin stream 1720-B comingfrom the last reactor of the stirred tank reactors. Optionally, wetgrinding 2010 of lignin prior to washing is conducted. The wet grinding2010 contributes to an increase in washing efficiency.

The lignin washing process 2020 can use various numbers of washingstages (e.g., two washing stages). In some method, 2-9 or 3-10 washingstages are used. Each washing stage can consist of a separator (e.g., ahydroclone, screen, filter, membranes) where the mixture of acid, sugar,and lignin solids is separated with the liquid stream moving to theprevious stage and the concentrated lignin solids stream moving to thenext stage of washing. The temperature of each washing stage can be thesame or different. For example, the last stage can be conducted at aslightly elevated temperature as compared to early reactors, e.g. 25°C.-40° C. versus 10° C.-20° C. Preferably, the method uses a 7-stagecounter-current system.

In some methods, each washing stage is carried out in a hydro-cyclone.The pressure in the hydro-cyclones can be 40 to 90 psig. In somemethods, two wash streams serve more than two hydro-cyclones. Forexample, the first wash stream has an HCl concentration of 40 to 43% andthe second wash stream has an HCl concentration of 32 to 36%. The firstwash stream can enter the first hydro-cyclone and the second wash streamenters the last hydro-cyclone. Optionally, washing temperature increasesas HCl concentration decreases in the wash.

Preferably, the wash system is counter current with an azeotropic acidsolution added to the last washing stage. The lignin containing freesugars and concentrated acid enters the first washing stage. Use ofazeotropic concentration is advantageous as it does not dilute thesolution with water, that later necessitates re-concentration of theacid solution at increased cost.

Optionally, the wash system is counter current with a weak acid wash(5-20% HCl concentration) added to the last washing stage. The lignincontaining free sugars and concentrated acid enters the first washingstage.

The multi stage washing process can remove up to 99% of the free sugarsand 90% of the excess acid entering the washing process with the lignin.The washed lignin leaves the last stage for further processing.

As discussed above in connection with acid recovery during sugarrefining process, the acid-loaded extractant can be back-extracted withwater to recover the acids. The recovered acid stream contains about15-23% acids at a temperature around 50° C. Preferably, this recoveredacid stream is used for lignin washing.

The exiting acid stream from lignin washing can contain up to 38-42%acid, which can be recycled in hydrolysis.

The lignin exiting lignin washing can contain 0.5-1.5% sugars. Thelignin can be pressed to remove excess liquid. The pressed lignin cancontain up to 35-50% solids, and preferably less than 1% residual sugarsand 13-20% HCl.

2. Deacidification

The washed (and optionally pressed) lignin 2020-A is then deacidified bycontacting with a hydrocarbon solvent 2040-A (process 2040 in FIG. 20).Optionally, wet grinding 2030 prior to contacting is conducted. The wetgrinding contributes to an increase in efficiency of de-acidification.This increased efficiency is in terms of a reduced time for contactingand/or a reduction in the ratio of wash stream to feed stream.

Various hydrocarbon solvents can be used. Preferably, the hydrocarbonhas a boiling point at atmospheric pressure between 100-250° C.,120-230° C., or 140-210° C. Examples of hydrocarbons suitable for thepresent invention include dodecane and various isoparaffinic fluids(e.g. ISOPAR G, H, J, K, L or M from ExxonMobil Chemical, USA). In somemethods, the selected isoparaffinic fluid is substantially insoluble inwater.

In some deacidification processes, the hydrocarbon solvent is mixed withlignin to make a slurry. For example, the hydrocarbon solvent is mixedwith lignin in a ratio of hydrocarbon (e.g., Isopar K) to dry lignin isabout 7/1; 9/1; 11/1; 15/1; 30/1; 40/1 or 45/1 w/w (or intermediate orgreater ratios). Preferably, 9 parts of hydrocarbon (e.g., Isopar K) arecontacted with 1 part of washed lignin stream (e.g. about 20% solidlignin on as is basis).

The mixture is then evaporated to remove acid from the slurry. The acidevaporates together with the hydrocarbon solvent. The evaporated acidcan be recovered and recycled in the hydrolysis process.

De-acidified lignin stream can include less than 2%, 1.5%, 1.0%, 0.5%,0.3%, 0.2% or 0.1% HCl. De-acidified lignin stream can contain at least60%, 70%, 80%, 90%, 95%, 96%, 97%, 98% or 99% solid lignin.

Optionally, the de-acidified lignin is dried to remove the hydrocarbonsolvent. Preferably, the dried, de-acidified lignin has less than 5%solvent and less than 0.5% acid.

VII. Lignin Refining

The dried, de-acidified lignin can be pelletized to make fuel pellets,or it can be further processed to produce novel lignin compositions asdescribed below. An exemplary method of lignin refining according tosome embodiments of the present invention is provided in FIG. 21(process 2100).

1. Alkali Solubilization

According to some exemplary embodiments of the present invention, thelignin (e.g., the de-acidified lignin) is solubilized to generate anaqueous lignin solution. For example, the lignin can be solubilized by apulping, a milling, a biorefining process selected from kraft pulping,sulfite pulping, caustic pulping, hydro-mechanical pulping, mild acidhydrolysis of lignocellulose feedstock, concentrated acid hydrolysis oflignocellulose feedstock, supercritical water or sub-supercritical waterhydrolysis of lignocellulose feedstock, ammonia extraction oflignocellulose feedstock. Preferably, the lignin is solubilized using analkaline solution. In one exemplary embodiment as shown in FIG. 19, thedeacidified lignin 2040-B or the dried, de-acidified lignin 2050-A isdissolved in an alkali solution to form an alkaline lignin solution2110-A. The alkali solubilization 2110 can be conducted at a temperaturegreater than 100° C., 110° C., 120° C. or 130° C., or lower than 200°C., 190° C., 180° C., 170° C., 160° C. or 150° C. Preferably, the alkalisolubilization 2110 is conducted at 160-220° C., 170-210° C., 180-200°C., or 182-190° C. The reaction can be conducted for a duration of atleast 10, 20, 30, 40, 50, 60, 70, 80, 90 or 120 minutes, or less than10, 9, 8, 7, 6, 5.5, 5, 4.5, 4 or 3.5 hours. Preferably, the alkalisolubilization 2110 is conducted for about 6 hours (e.g. at 182° C.). Anincrease in cooking time and/or in cooking temperature contributes to anincrease in lignin fragmentation and/or degradation.

An alkaline concentration of at least 5%, 6%; 7%, 8%, 9%, 10%, 11%, 12%,13%, 14%, 15% or intermediate or greater percentages (when expressed as100× base/(base+water) on a weight basis) can be used for alkalisolubilization. Optionally, alkali solution includes ammonia and/orsodium hydroxide and/or sodium carbonate.

Upon alkali solubilization, residual hydrocarbon (e.g. IsoPar K ordodecane) from dc-acidification separates easily into a separate organicphase which is decanted and recycled.

2. Limited-Solubility Solvent Purification

The aqueous lignin solution (e.g., the alkaline lignin solution) can beprocessed to prepare novel high-purity lignin material using alimited-solubility solvent (process 2120 in FIG. 21). It wassurprisingly discovered lignin can be dissolved in a limited-solubilitysolvent 2120-B (e.g., methyl ethylketone), and that the lignin purifiedusing a limited-solubility solvent has unexpected, superior properties.In some embodiments, the limited-solubility solvent is an organicsolvent having a solubility in water at 20° C. of less than about 30% wtsolvent in water.

For example, the alkaline solution can be contacted with an acidulant2120-A (e.g., HCl) and simultaneously or subsequently mixed with alimited-solubility solvent 2120-B to form a two phase system containingacidic lignin. Various acidulants known in the art can be used to adjustthe pH of the alkaline solution to less than 7.0, 6.0, 5.0, 4.0, 3.0,2.0, or 1.0. Preferably, the pH is about 4.0, e.g., ˜3.5-4.0. Theacidulant 2120-A converts basic lignin into acidic lignin. The lignindissolves into the solvent phase whereas water soluble impurities andsalts stay in the aqueous phase. The lignin in the solvent phase can bewashed with water and optionally purified using a strong acid cationexchanger to remove residual cations.

The limited-solubility solvent should have low solubility in water,solubility at room temperature should be less than 35% wt, less than 28%wt, less than 10% wt. The solvent should form two phases with water, andthe solubility of water in it should be up to 20%, up to 15%, up to 10%up to 5% at room temperature. Preferably the solvent should be stable atacidic conditions at temperature up to 100° C. Preferably, the solventshould form a heterogeneous azeotrope with water, having a boiling pointof less than 100° C. where the azeotrope composition contains at least50% of the solvent, at least 60% of the solvent out of total azeotrope.The solvent should have a least one hydrophilic functional groupselected from ketone, alcohol and ether or other polar functional group.Preferably said solvent should be commercially available at low cost.

Examples of solvents suitable for the present invention includemethylethylketone, methylisobutylketone, diethylketone, methyl isopropylketone, methylpropylketone, mesityl oxide, diacetyl, 2,3-pentanedione,2,4-pentanedione, 2,5-dimethylfuran, 2-methylfuran, 2-ethylfuran,1-chloro-2-butanone, methyl tert-butyl ether, diisopropyl ether, anisol,ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate, propylacetate, propyl formate, isopropyl formate, 2-phenylethanol, toluene,1-phenylethanol, phenol, m-cresol, 2-phenylethyl chloride,2-methyl-2H-furan-3-one, γ-butyrolactone, acetal, methyl ethyl acetal,dimethyl acetal. Optionally, the limited-solubility solvent includes oneor more of esters, ethers and ketones with 4 to 8 carbon atoms.

To obtain high purity solid lignin, the limited-solubility solvent isseparated from lignin (process 2140 in FIG. 21). For example, thelimited-solubility solvent can be evaporated. Preferably, thelimited-solubility solvent can be separated from lignin by mixing thesolvent solution containing acidic lignin with water at an elevatedtemperature (e.g., 75° C., 85° C., 90° C.). The precipitated lignin canbe recovered by, e.g., filtration or centrifugation. The solid lignincan be dissolved in any suitable solvents (e.g., phenylethyl alcohol)for making lignin solutions.

Alternatively, the limited-solubility solvent solution containing acidiclignin can be mixed with another solvent (e.g., toluene). Thelimited-solubility solvent can be evaporated whereas the replacementsolvent (e.g., toluene) stays in the solution. A lignin solution in adesired solvent can be prepared.

3. High Purity Lignin

The high purity lignin obtained using the limited-solubility solventpurification method has unexpected and superior properties over naturallignins. It was discovered that the high purity lignin has low aliphatichydroxyl group and high phenolic hydroxyl group, indicating cleavage orcondensation along the side chain and condensation between phenolicmoieties. The high purity lignin of the invention is more condensed ascompared to natural lignins or other industrial lignins. It has lessmethoxyl content and aliphatic chains and a very high degree ofdemethylation.

In some embodiments, the high purity lignin is characterized by one ormore, two or more, three or more, four or more, five or more, six ormore, seven or more, eight or more, nine or more, ten or more, eleven ormore, twelve or more, thirteen or more, fourteen or more, fifteen ormore, sixteen or more, seventeen or more, eighteen or more,characteristics including (a) lignin aliphatic hydroxyl group in anamount up to 2 mmole/g; (b) at least 2.5 mmole/g lignin phenolichydroxyl group; (c) at least 0.35 mmole/g lignin carboxylic hydroxylgroup; (d) sulfur in an amount up to 1% weight/weight; (e) nitrogen inan amount up to 0.05% weight/weight; (f) chloride in an amount up to0.1% weight/weight; (g) 5% degradation temperature higher than 250° C.;(h) 10% degradation temperature higher than 300° C.; (i) low ashcontent; (j) a formula of CaHbOc; wherein a is 9, b is less than 10 andc is less than 3; (k) a degree of condensation of at least 0.9; (l) amethoxyl content of less than 1.0; (m) an O/C weight ratio of less than0.4, (n) at least 97% lignin on a dry matter basis; (o) an ash contentin an amount up to 0.1% weight/weight; (p) a total carbohydrate contentin an amount up to 0.05% weight/weight; (q) a volatiles content in anamount up to 5% weight/weight at 200° C.; and (r) a non-meltingparticulate content in an amount up to 0.05% weight/weight.

In some embodiments, the high purity lignin is characterized by one ormore, two or more, three or more, four or more, five or more,characteristics including (a) at least 97% lignin on a dry matter basis;(b) an ash content in an amount up to 0.1% weight/weight; (c) a totalcarbohydrate content in an amount up to 0.05% weight/weight; (d) avolatiles content in an amount up to 5% weight/weight at 200° C.; and(e) a non-melting particulate content in an amount up to 0.05%weight/weight. For example, the high purity lignin can be a lignincharacterized by (a) at least 97% lignin on a dry matter basis; (b) anash content in an amount up to 0.1% weight/weight; (c) a totalcarbohydrate content in an amount up to 0.05% weight/weight; and (d) avolatiles content in an amount up to 5% weight/weight at 200° C.

In some embodiments, the high purity lignin of the invention has a highpurity. In some cases, the high purity lignin is more than 80, 85, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 99.5, 99.7, or 99.9% pure. In someembodiments, the high purity lignin of the invention has a low ashcontent. In some cases, the high purity lignin has an ash content in anamount up to 5, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.05,0.02, 0.01% weight/weight. In some embodiments, the high purity ligninof the invention has a low carbohydrate content. In some case, the highpurity lignin has a total carbohydrate content in an amount up to 0.005,0.0075, 0.01, 0.015, 0.020, 0.025, 0.030, 0.035, 0.04, 0.045, 0.05,0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0% weight/weight. Insome cases, the high purity lignin has a volatile content at 200° C. inan amount up to 0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10%weight/weight.

In some embodiments, the high purity lignin of the invention has a lownon-melting particulate content. In some cases, the high purity ligninhas a non-melting particulate content in an amount up to 0.005, 0.0075,0.01, 0.015, 0.020, 0.025, 0.030, 0.035, 0.04, 0.045, 0.05, 0.06, 0.07,0.08, 0.09, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0% weight/weight.

In some embodiments, the high purity lignin is characterized by one ormore, two or more, three or more, four or more, five or more, six ormore, seven or more, eight or more, nine or more, ten or more, eleven ormore, twelve or more, thirteen or more, characteristics including (a)lignin aliphatic hydroxyl group in an amount up to 2 mmole/g; (b) atleast 2.5 mmole/g lignin phenolic hydroxyl group; (c) at least 0.35mmole/g lignin carboxylic hydroxyl group; (d) sulfur in an amount up to1% weight/weight; (e) nitrogen in an amount up to 0.05% weight/weight;(f) chloride in an amount up to 0.1% weight/weight; (g) 5% degradationtemperature higher than 250° C.; (h) 10% degradation temperature higherthan 300° C.; (i) low ash content; (j) a formula of CaHbOc; wherein a is9, b is less than 10 and c is less than 3; (k) a degree of condensationof at least 0.9; (l) a methoxyl content of less than 1.0; and (m) an O/Cweight ratio of less than 0.4. For example, the high purity lignin canbe a lignin characterized by (a) lignin aliphatic hydroxyl group in anamount up to 2 mmole/g; (b) at least 2.5 mmole/g lignin phenolichydroxyl group; and (c) at least 0.35 mmole/g lignin carboxylic hydroxylgroup. In some embodiments, the high purity lignin is characterized by(a) lignin aliphatic hydroxyl group in an amount up to 2 mmole/g; (b) atleast 2.5 mmole/g lignin phenolic hydroxyl group; (c) at least 0.35mmole/g lignin carboxylic hydroxyl group, (d) sulfur in an amount up to1% weight/weight, (e) and nitrogen in an amount up to 0.05%weight/weight. In some embodiments, the high purity lignin ischaracterized by (a) less than 2 mmole/g lignin aliphatic hydroxylgroup; (b) at least 2.5 mmole/g lignin phenolic hydroxyl group; (c) atleast 0.35 mmole/g lignin carboxylic hydroxyl group, (d) sulfur in anamount up to 1% weight/weight, (e) nitrogen in an amount up to 0.05%weight/weight and (f) chloride in an amount up to 0.1% weight/weight. Insome embodiments, the high purity lignin is characterized by its thermaldegradation properties, e.g., a higher than 250° C. 5% degradationtemperature; a higher than 300° C. 10% degradation temperature. In someembodiments, the high purity lignin is characterized by a formula ofCaHbOc; wherein a is 9, b is less than 10 and c is less than 3, a degreeof condensation of at least 0.9, a methoxyl content of less than 1.0,and an O/C weight ratio of less than 0.4. In other embodiments, the highpurity lignin is characterized by an O/C weight ratio of less than 0.40,0.39, 0.38, 0.37, 0.36, 0.35, 0.34, 0.33, 0.32, 0.31, 0.30, 0.29, 0.28,0.27, 0.26, 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, or 0.20-0.22, 0.22-0.24,0.24-0.26, 0.26-0.28, 0.28-0.30, 0.32-0.34, 0.34-0.36, 0.36-0.38, or0.38-0.40.

In some embodiments, the high purity lignin of the invention has a lowcontent of aliphatic hydroxyl group. In some cases, the high puritylignin has lignin aliphatic hydroxyl group in an amount up to 0.1, 0.2,0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.2, 1.4, 1.6, 1.8, 1.9, or 2.0mmole/g. In some embodiments, the high purity lignin of the inventionhas a high content of lignin phenolic hydroxyl group. In some cases, thehigh purity lignin has more than 2.0, 2.2, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9,3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4.0 mmole/g ligninphenolic hydroxyl group. In some embodiments, the high purity lignin ofthe invention has a high content of lignin carboxylic hydroxyl group. Insome cases, the high purity lignin has more than 0.20, 0.25, 0.30, 0.35,0.40, 0.45, 0.50, 0.60, 0.70, 0.80, 0.90, 1.0 mmole/g lignin carboxylichydroxyl group. In some embodiments, the high purity lignin of theinvention has a low content of aliphatic hydroxyl group, a high contentof lignin phenolic hydroxyl group, and a high content of lignincarboxylic hydroxyl group. In some cases, the high purity lignin of theinvention has lignin aliphatic hydroxyl group in an amount up to 2mmole/g, at least 2.5 mmole/g lignin phenolic hydroxyl group, and atleast 0.35 mmole/g lignin carboxylic hydroxyl group. In some cases, thehigh purity lignin of the invention has lignin aliphatic hydroxyl groupin an amount up to 1 mmole/g, at least 2.7 mmole/g lignin phenolichydroxyl group, and at least 0.4 mmole/g lignin carboxylic hydroxylgroup. In some cases, the high purity lignin of the invention has ligninaliphatic hydroxyl group in an amount up to 0.5 mmole/g, at least 3.0mmole/g lignin phenolic hydroxyl group, and at least 0.9 mmole/g lignincarboxylic hydroxyl group.

In some embodiments, the high purity lignin of the invention has a lowcontent of sulfur. In some cases, the high purity lignin has sulfur inan amount up to 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.5,2, 2.5, 3, 3.5, 4, 4.5, 5.0, 10.0% weight/weight. In some embodiments,the high purity lignin of the invention has a low content of nitrogen.In some cases, the high purity lignin has nitrogen in an amount up to0.005, 0.0075, 0.01, 0.015, 0.020, 0.025, 0.030, 0.035, 0.04, 0.045,0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0%weight/weight. In some embodiments, the high purity lignin of theinvention has a low content of chloride. In some cases, the high puritylignin has chloride in an amount up to 0.01, 0.02, 0.05, 0.10, 0.15,0.20, 0.25, 0.5, 0.75, 1.0, 2.0% weight/chloride. In some embodiments,the high purity lignin of the invention has a low ash content.

The high purity lignin of the invention also has superior thermalproperties such as thermal stability. In some embodiments, the highpurity lignin of the invention has a 5% degradation temperature higherthan 100, 150, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, or 300°C. In some embodiments, the high purity lignin of the invention has a10% degradation temperature higher than 200, 250, 275, 280, 290, 300,310, 320, 330, 340, 350, 360, 370, 380, 390, or 400° C.

In some embodiments, the high purity lignin of the invention can becharacterized by a formula of CaHbOc; wherein a is 9, b is less than 10and c is less than 3. In some cases, b less than 9.5, 9.0, 8.5, 8.0,7.5, or 7.0. In some cases, c is less than 2.9, 2.7, 2.6, or 2.5. Inother embodiments, the high purity lignin is characterized by an O/Cweight ratio of less than 0.40, 0.39, 0.38, 0.37, 0.36, 0.35, 0.34,0.33, 0.32, 0.31, 0.30, 0.29, 0.28, 0.27, 0.26, 0.25, 0.24, 0.23, 0.22,0.21, 0.20, or 0.20-0.22, 0.22-0.24, 0.24-0.26, 0.26-0.28, 0.28-0.30,0.32-0.34, 0.34-0.36, 0.36-0.38, or 0.38-0.40.

In some embodiments, the high purity lignin of the invention has a highdegree of condensation. In some cases, the high purity lignin of theinvention has a degree of condensation of at least 0.7, 0.8, 0.9, 0.95,1.0, 1.1, 1.2, 1.3, 1.4, or 1.5. In some embodiments, the high puritylignin of the invention is characterized with a low a methoxyl content.In some cases, the high purity lignin of the invention has a methoxylcontent of less than 1.0, 0.9, 0.8, 0.7, 0.6, or 0.5.

4. Downstream Processing

Exemplary Anti-Solvent Processing:

In some embodiments, an anti-solvent is used for desolventization. Forexample, methyl-ethyl ketone (MEK) has a solubility of 27.5 gram in 100gram aqueous solution (the acidic lignin dissolved in alimited-solubility solvent which is MEK in this embodiment). In someembodiments, spraying lignin dissolved in MEK into water (e.g. atambient temperature) dissolves the MEK in the water. The solubility oflignin in the MEK water mixture (at appropriate water:MEK ratio) is lowso that lignin precipitates. In some embodiments, MEK is separated fromthe mixture by distilling its azeotrope (73.5° C., 89% MEK).

Each solvent/anti-solvent combination represents an additionalembodiment of the invention. Exemplary solvent/anti-solvent combinationsinclude MEK-water; MEK-decanol and MEK-decane.

Exemplary Processing by Distillation:

In some embodiments limited-solubility solvent (e.g. MEK; boilingpoint=79.6° C.) is distilled away from the lignin dissolved in it. Insome embodiments, the distillation includes contacting thelimited-solubility solvent with lignin dissolved in it with a hot gas(e.g. spray drying). Optionally contacting with a hot gas is conductedafter a pre-evaporation which increases the lignin concentration in thelimited-solubility solvent. In some embodiments, the distillationincludes contacting the limited-solubility solvent with lignin dissolvedin it with a hot liquid. In some embodiments, the contacting includesspraying the limited-solubility solvent with lignin dissolved in it intoa hot liquid (optionally after some pre-concentration). In someembodiments, the hot liquid includes water and/or oil and/or Isopar K.In some embodiments, the hot liquid includes an anti-solvent. In someembodiments, the distillation includes contacting the limited-solubilitysolvent with lignin dissolved in it with a hot solid surface.

In some embodiments, a hot liquid is contacted with thelimited-solubility solvent with lignin dissolved in it.Hydrophilic/hydrophobic properties of the hot liquid affect the surfaceproperties of the separated solid lignin. In some embodiments, in thosedistillation embodiments which employ contacting the limited-solubilitysolvent with lignin dissolved in it with a hot liquid, the chemicalnature of the lignin solvent affects the surface properties of theseparated solid lignin. In some embodiments, the hot liquid influencesthe nature and availability of reactive functions on the separated solidlignin. In some embodiments, the nature and availability of reactivefunctions on the separated solid lignin contribute to efficiency ofcompounding, e.g. with other polymers. In some embodiments, atemperature of the hot liquid influences the molecular weight of theseparated solid lignin.

Exemplary Spinning Processes:

In some embodiments, spraying lignin dissolved in limited-solubilitysolvent into a hot liquid and/or contacting with an anti-solvent producelignin in a form suitable for wet spinning. These processes can beadapted to produce lignin in a form suitable for wet spinning byadjusting various parameters such as, for example, absolute and/orrelative temperatures of the two liquids and/or the concentration oflignin dissolved in the limited-solubility solvent. In some embodiments,the concentration of lignin dissolved in the limited-solubility solventcontributes to viscosity of the lignin/solvent solution.

Exemplary Modifying Reagents:

In some embodiments, the hot liquid with which the lignin dissolved inlimited-solubility solvent is contacted includes a modifying reagent.Optionally, the hot liquid is the modifying reagent. In someembodiments, upon contact with the hot liquid, lignin reacts with and/oris coated by the modifying reagent.

Exemplary Coating Processes:

Some exemplary embodiments in which distillation is accomplished bycontacting the lignin dissolved in limited-solubility solvent with a hotsolid surface result in coating of the solid surface with a ligninlayer. According to some embodiments such coating serves to encapsulatethe solid surface. Encapsulation of this type is useful, for example, inslow-release fertilizer formulation and/or in provision of a moisturebarrier. In some embodiments, the solid to be coated is provided asfibers. The resultant coated fibers are useful, for example, in themanufacture of composite materials. In some embodiments, the lignin isdissolved in a volatile solvent (e.g. MEK). Use of a volatilelimited-solubility solvent contributes to a capacity for coating ofthermally sensitive solids. In some embodiments, a plasticizer is addedto the lignin dissolved in limited-solubility solvent. Optionally, theplasticizer contributes to an improvement in the resultant coating.

Polymer Organization:

In some embodiments, the lignin dissolved in limited-solubility solventis co-sprayed with a second polymer that has a linear arrangement tocause formation of rod like assemblies of lignin molecules. Resultantco-polymer arrangements with a high aspect ratio are useful instructural applications (e.g. carbon fibers).

VIII. Direct Lignin Extraction from Lignocellulosic Biomass

As discussed above in connection with hemicellulose sugars extraction,the present invention in one aspect provides a novel method ofextracting lignin directly from lignocellulosic biomass afterhemicellulose sugars are extracted. The method utilizes alimited-solubility solvent, and works well with biomass particles ofvarious sizes. Therefore, it is not necessary to grind the particlesprior to lignin extraction.

The extraction of hemicellulose sugars from the biomass results in alignin-containing remainder. In some methods, the extraction ofhemicellulose sugars does not remove a substantial amount of thecellulosic sugars. For example, the extraction of hemicellulose sugarsdoes not remove more than 1, 2, 5, 10, 15, 20, 30, 40, 50, 60%weight/weight cellulose. In some methods, the lignin-containingremainder contains lignin and cellulose. In some methods, thelignin-containing remainder contains less than 50, 45, 40, 35, 30, 25,20, 15, 10, 5, 2, 1% hemicellulose. In some embodiments, the lignin canbe directly extracted from lignocellulosic biomass without removinghemicellulose sugars.

The lignin extraction solution contains a limited-solubility solvent, anacid, and water. Examples of limited-solubility solvents suitable forthe present invention include methylethylketone, diethylketone, methylisopropyl ketone, methyl propyl ketone, mesityl oxide, diacetyl,2,3-pentanedione, 2,4-pentanedione, 2,5-dimethylfuran, 2-methylfuran,2-ethylfuran, 1-chloro-2-butanone, methyl tert-butyl ether, diisopropylether, anisol, ethyl acetate, methyl acetate, ethyl formate, isopropylacetate, propyl acetate, propyl formate, isopropyl formate,2-phenylethanol, toluene, 1-phenylethanol, phenol, m-cresol,2-phenylethyl chloride, 2-methyl-2H-furan-3-one, γ-butyrolactone,acetal, methyl ethyl acetal, dimethyl acetal, morpholine, pyrrol,2-picoline, 2,5-dimethylpyridine. Optionally, the limited-solubilitysolvent includes one or more of esters, ethers and ketones with 4 to 8carbon atoms. For example, the limited-solubility solvent can includeethyl acetate. Optionally, the limited-solubility solvent consistsessentially of, or consists of, ethyl acetate.

The ratio of the limited-solubility solvent to water suitable forcarrying out the lignin extraction can vary depending on the biomassmaterial and the particular limited-solubility solvent used. In general,the solvent to water ratio is in the range of 100:1 to 1:100, e.g.,50:1-1:50, 20:1 to 1:20, and preferably 1:1.

Various inorganic and organic acids can be used for lignin extraction.For example, the solution can contain an inorganic or organic acid suchas H₂SO₄, HCl, acetic acid and formic acid. The acidic aqueous solutioncan contain 0 to 10% acid or more, e.g., 0-0.4%, 0.4-0.6%, 0.6-1.0%,1.0-2.0%, 2.0-3.0%, 3.0-4.0%, 4.0-5.0% or more. Preferably, the aqueoussolution for the extraction and hydrolysis includes 0.6-5%, preferably1.2-1.5% acetic acid. The pH of the acidic aqueous solution can be, forexample, in the range of 0-6.5.

Elevated temperatures and/or pressures are preferred in ligninextraction. For example, the temperature of lignin extraction can be inthe range of 50-300° C., preferably 160 to 200° C., e.g., 175-185° C.The pressure can be in the range of 1-10 mPa, preferably, 1-5 mPa. Thesolution can be heated for 0.5-24 hours, preferably 1-3 hours.

Lignin is extracted in the limited-solubility solvent (organic phase),the remaining solid contains mostly cellulose. After the solid phase iswashed to remove residual lignin, the cellulose can be used to producepulp, or as starting material for hydrolysis (acidic or enzymatic). Anexemplary method of hydrolysis of cellulose by cellulase according tosome embodiments of the present invention is shown in FIG. 22. In someexemplary embodiments, cellulose hydrolysis and cellulose sugar refiningcan be carried out under conditions identical or similar to thosedescribed above in sections IV and V. The residual lignin can beprocessed and refined using procedures described above in sections VIand VII.

Optionally, the pH of the solvent is adjusted to 3.0 to 4.5 (e.g.,3.5-3.8). At this pH range, the lignin is protonated and is easilyextracted into the organic phase. The organic phase comprising solventand lignin is contacted with strong acid cation exchanger to removeresidual metal cations. To obtain high purity solid lignin, thelimited-solubility solvent is separated from lignin, e.g., evaporated.Preferably, the limited-solubility solvent can be separated from ligninby mixing the solvent solution containing acidic lignin with water at anelevated temperature (e.g., 80° C.). The precipitated lignin can berecovered by, e.g., filtration or centrifugation. The solid lignin canbe dissolved in any suitable solvents (e.g., phenylethyl alcohol) formaking lignin solutions.

Alternatively, the limited-solubility solvent solution containing acidiclignin can be mixed with another solvent (e.g., toluene). Thelimited-solubility solvent can be evaporated whereas the replacementsolvent (e.g., toluene) stays in the solution. A lignin solution in adesired solvent can be prepared.

FIG. 43 is a schematic description of a process for acid-solventextraction of lignin from hemicellulose depleted lignocellulose matterand for the refining of the solvent-soluble lignin according to certainembodiments of the invention. This process results in stream 200,comprising the solvent and dissolved lignin, where residual ash is lessthan 1000 ppm, preferably less than 500 ppm, wherein polyvalent cationsare less than 500 ppm, preferably less than 200 ppm relative to lignin(on dry base) and residual carbohydrate is less than 500 ppm relative tolignin (on dry base). The solution is free of particulate matter.

IX. Waste Water Treatment

To utilize the energy stored in organic solutes and to comply withenvironmental requirements, aqueous waste streams that contain organicmatter can be treated in anaerobic digesters to produce methane, whichcan be burned. However, anaerobic digesters are known to be poisoned bytoo high levels of sulfate ions per a given chemical oxygen demand (COD)level, and are also limited to the incoming stream having less than 400ppm calcium ions to prevent calcium carbonate build up in the digester.The aqueous waste streams produced in various stages of the currentinvention as described above comply with these requirements.Furthermore, as disclosed above, back extraction may be conducted inseveral steps allowing better control of the inorganic ion level versusthe organic matter.

X. Lignin Applications

The high purity lignin composition according to embodiments disclosedherein has a low ash content, a low sulfur and/or phosphorousconcentration. Such a high purity lignin composition is particularlysuitable for use in catalytic reactions by contributing to a reductionin catalyst fouling and/or poisoning A lignin composition having a lowsulfur content is especially desired for use as fuel additives, forexample in gasoline or diesel fuel.

Some other potential applications for high purity lignin includecarbon-fiber production, asphalt production, and as a component inbiopolymers. These uses include, for example, oil well drillingadditives, concrete additives, dyestuffs dispersants, agriculturechemicals, animal feeds, industrial binders, specialty polymers forpaper industry, precious metal recovery aids, wood preservation,sulfur-free lignin products, automotive brakes, wood panel products,bio-dispersants, polyurethane foams, epoxy resins, printed circuitboards, emulsifiers, sequestrants, water treatment formulations,strength additive for wallboard, adhesives, raw materials for vanillin,xylitol, and as a source for paracoumaryl, coniferyl, sinapyl alcohol.

Disclosed in Sections XI-XIV are additional embodiments of theinvention.

XI. Alternative Lignocellulosic Biomass Processing and Acid RecoveryEmbodiments

Embodiments disclosed in this section in general relate to processing ofa lignocellulosic substrate to produce sugars and/or lignin, and acidrecovery (e.g., HCl recovery).

For example, some embodiments disclosed herein can be used to produce anHCl solution with a concentration greater than 37% by back-extractingHCl from an S1 solvent based extractant to generate a sub-azeotropic HClsolution, followed by distillation at greater than atmospheric pressureto generate HCl gas. The HCl gas is then absorbed by the sub-azeotropicHCl solution to produce an HCl solution with a concentration greaterthan 37%.

First Exemplary Method

FIG. 23 is a simplified flow scheme of a method according to someembodiments. In FIG. 23, dashed lines indicate a flow of solvent andsolid lines indicate a flow of HCl (gas or aqueous solution) and/orsugars and/or lignin.

The depicted exemplary method includes, hydrolyzing 110 alignocellulosic material (not depicted) with a recycled HCl stream (e.g.from 130 and/or 160) to form an aqueous hydrolysate (which progressesdownwards from 110 in the drawing) and a solid lignin stream (i.e. astream including solid lignin which progresses rightwards from 110 inthe drawing). Optionally, the solid lignin stream is subjected togrinding (e.g. after 110 and before 160). In some embodiments, thehydrolysate includes a sugar mixture and HCl at more than 20%, 25%, 26%,27%, 28%, 29%, 30%, 31%, 32%, 33%, 34% or 35% weight/weight HCl/[HCl andwater] and/or the lignin stream includes HCl at more than 25%, 26%, 27%,28%, 29%, 30%, 31%, 32%, 33%, 34% or 35% weight/weight HCl/[HCl andwater].

The depicted exemplary method also includes extracting (120A and/or120B) the hydrolysate with a recycled extractant including an S1solvent. The extraction involves at least two extraction steps (120A and120B). In some embodiments, the extract from 120A includes more than20%, more than 25%, more than 30%, more than 35% or 40% weight/weight ormore HCl/[HCl and water]. Due to the nature of S1 solvents, acid andwater are preferentially extracted over sugars.

Optionally, the method includes increasing a monomeric sugar tooligomeric sugar ratio in the sugar mixture (e.g. by secondaryhydrolysis 124) and polishing (e.g. by chromatography 128) the mixtureto produce a polished mixture (129) containing at least 70%, at least75%, at least 80%, at least 85%, at least 90% or at least 95%weight/weight monomeric sugars out of total sugars and less than 1%,less than 0.7%, less than 0.5%, less than 0.3, less than 0.1% or lessthan 0.01% weight/weight HCl on as is basis. In some embodiments,increasing a monomeric sugar to oligomeric sugar ratio in the sugarmixture includes chromatographic separation 128 to separate a monomercut from an oligomer cut. In some embodiments, the monomer cut isharvested as polished sugars 129 and the oligomer cut is recycled tosecondary hydrolysis 124 as indicated by the upward arrow from 128 to124.

Treatment of the sugar mixture from hydrolysis 110 by extractions 120Aand 120B in conjunction with secondary hydrolysis 124 and chromatography128 is described in PCT/US2012/024033 (incorporated herein by referencefor all purposes).

The depicted exemplary method also includes back-extracting (e.g. 130and/or 132) the extract with an aqueous solution to form a de-acidifiedextractant and an aqueous back-extract. The aqueous solution can bewater. The aqueous solution can also include one or more solutes.

The depicted exemplary method also includes incorporating thede-acidified extractant into the recycled extractant (dashed line from132 to 120B). In some embodiments, at least a portion of the extractantis diverted to purification 135. Exemplary methods for purification 135are described in PCT/US2011/046153 (incorporated herein by reference forall purposes).

The depicted exemplary embodiment includes evaporating 111 a mixture ofwater and HCl from the hydrolysate prior to extracting (120A and/or120B). In some embodiments, the evaporated mixture goes to absorber 150.In some embodiments at least a portion of the evaporated mixture iscondensed and routed to high-pressure evaporator 142 (See FIG. 24).Optionally, routing of the evaporated mixture to absorber 150contributes to a reduction in energy consumption at evaporation module145. In some embodiments, a reduction in volume of liquid or a reductionin HCl concentration of the stream from 120A to 130 contributes to thereduction in energy consumption at 145. In some embodiments, at least aportion of the mixture of water and HCl from evaporating 111 (afterpassing through absorber 150) washes the solid lignin stream (e.g. at162 and/or 160).

In some embodiments, the aqueous back-extract produced at 130 isincorporated into the recycled HCl stream arriving at hydrolysis 110. Insome embodiments, the back extract from 130 returns to extraction 120A(see FIG. 24).

In some embodiments, the increasing includes at least one ofchromatographic separation 128 and acid-catalyzed (secondary) hydrolysis124 of oligomeric sugars. Optionally, the increasing includes bothchromatographic separation 128 and acid-catalyzed hydrolysis 124 ofoligomeric sugars.

In some embodiments, oligomeric sugars are hydrolyzed to monomericsugars (124) between a pair of the at least two extraction steps (e.g.120A and 120B). In other embodiments, the method includes hydrolyzingoligomeric sugars to monomeric sugars (124) after the extraction step/sor prior to the extraction step/s (not depicted). In some embodiments,hydrolysis 124 is catalyzed by acid remaining in the aqueous streamexiting extraction 120A. Optionally, the acid is further diluted by anaqueous stream from chromatography 128 which is delivered to hydrolysis124.

In some embodiments, the increasing includes chromatographic separation128 conducted on the mixture after extracting 120A and 120B. In someembodiments, the polishing includes chromatographic separation 128conducted on the mixture after extracting 120A and 120B. In someembodiments, the increasing and polishing include chromatographicseparation 128 conducted on the mixture after extracting 120A and 120B.Optionally, chromatographic separation 128 generates a sugar cut and anoligomer cut. In some embodiments, the sugar cut serves as polishedmixture 129 and the oligomer cut is enriched in oligomeric sugars. Insome embodiments, the oligomer cut is enriched in HCl. In someembodiments, chromatographic separation 128 contributes to bothincreasing and to polishing. In some embodiments, the increasingincludes acid-catalyzed hydrolysis 124 of oligomeric sugars and theoligomer cut is recycled to acid-catalyzed hydrolysis 124 (see arrowfrom 128).

In some embodiments the lignin stream contains sugars. The solid ligninstream is washed with at least a fraction of the back-extract or atleast a fraction of the dilute back extract. A washed lignin stream anda wash liquor are generated. The wash liquor is included as at least aportion of the recycled HCl stream. In FIG. 23, this occurs as theback-extract flows from 132 via absorber 150 to second lignin wash 162.The solid lignin flows forward from second lignin wash 162 tode-acidification 164 and the wash liquor proceeds backwards tohydrolysis 110 via first lignin wash 160. In some embodiments, the washliquor includes 70%, 75%, 80%, 85%, 90% or 95% weight/weight, orintermediate or greater percentages of the sugars originally present inthe lignin stream (prior to washing). In some embodiments, the solidlignin stream is washed with at least a portion of the mixture of waterand HCl from evaporating 111 (e.g. at 162 and/or 160). In someembodiments, the at least a portion of the mixture of water and HClpasses through absorber 150 prior to washing the lignin. Exemplarymethods for washing of a lignin stream with a re-cycled HCl stream aredescribed in greater detail in PCT/IL2011/000424 (incorporated herein byreference for all purposes). De-acidified lignin 165 contains less than0.5%, less than 0.3% or less than 0.2% weight/weight HCl.

In some embodiments, at least a fraction of the back-extract from 132 istreated in an evaporation module 145. Depicted exemplary evaporationmodule 145 includes at least one low-pressure evaporator 140 and atleast one high-pressure evaporator 142. In some embodiments, evaporationmodule 145 generates a sub-azeotropic acid condensate, andsuper-azeotropic gaseous HCl and the recycled HCl stream includes thegaseous HCl. Optionally, low-pressure evaporator 140 generates asub-azeotropic acid condensate. Optionally, high-pressure evaporator 142generates super-azeotropic gaseous HCl. In some embodiments, thesub-azeotropic acid condensate contains HCl in an amount up to 2%, 1%,0.1% or 0.01% weight/weight on as is basis. In some embodiments, therecycled HCl stream includes the gaseous HCl from 142 (e.g. afterabsorption into an aqueous solution at absorber 150).

In some embodiments, the solid lignin stream is washed with anotherfraction of the back-extract to generate a washed lignin stream and awash liquor. In some embodiments, this other fraction includes gaseousHCl from 142 which joins the back-extract from 132 at absorber 150 andproceeds to second lignin wash 162. In some embodiments, this otherfraction includes at least a portion of the mixture of water and HClfrom evaporating 111 which joins the back-extract from 132 at absorber150 and proceeds to second lignin wash 162.

In some embodiments, evaporation module 145 generates a super-azeotropicaqueous HCl solution and a sub-azeotropic aqueous HCl solution. In someembodiments, the at least one low-pressure evaporator 140 generates thesuper-azeotropic aqueous HCl solution and the at least one high-pressureevaporator 142 generates the sub-azeotropic aqueous HCl solution.

In some embodiments, the lignin stream is deacidified 164 to formde-acidified lignin and a de-acidification HCl stream, and incorporatingthe de-acidification HCl stream into the recycled HCl stream. In FIG. 23the de-acidification HCl stream proceeds via low-pressure distillation140 to high-pressure distillation 142. In some embodiments, gaseous HClfrom 142 is recycled to hydrolysis 110 via absorbers 150 and/or anaqueous flow of dilute liquid HCl is recycled to hydrolysis 110 via backextraction 130. In some embodiments, de-acidifying 164 is conducted inthe presence of an azeotropic HCl solution and/or a super-azeotropic HClsolution formed as bottoms of low-pressure distillation 140 and/or asub-azeotropic HCl solution formed as bottoms of high-pressuredistillation 142. In some embodiments, the de-acidification HCl streamfrom 164 is treated in evaporation module 145 containing a high-pressuredistillation to form a sub-azeotropic HCl solution and gaseous HCl andincorporating the gaseous HCl stream into the recycled HCl stream. Insome embodiments, high-pressure distillation unit 142 forms thesub-azeotropic HCl solution and the gaseous HCl stream.

In some embodiments, back-extracting 130 and/or 132 is conducted withwater and/or a dilute (sub-azeotropic) acid solution (e.g. formed as acondensate of low-pressure distillation 140) and/or a sub-azeotropic HClsolution (e.g. formed as bottoms of high-pressure distillation 142). Insome embodiments, the back-extracting is conducted in two stages (130and 132), a dilute stage and a concentrated stage. Optionally, thedilute stage is conducted with at least one of water and a dilute acidsolution (e.g. formed as a condensate of low-pressure evaporation 140).In some embodiments, the concentrated stage is conducted with at leastone of an azeotropic HCl solution, a super-azeotropic HCl solution (e.g.formed as bottoms of low-pressure evaporation 140) and a sub-azeotropicHCl solution (e.g. formed as bottoms of high-pressure evaporation 142).

In some embodiments, the extract from 120A goes first through aconcentrated-stage back-extraction 130 forming a concentratedback-extract and then through a dilute-stage back-extraction 132 forminga dilute back-extract. In some embodiments, the extract includes sugarsand the concentrated back-extract includes at least 70% of those sugars.Optionally, the method includes incorporating the concentratedback-extract into the recycled HCl stream (arrow from 130 to 110 in FIG.23). In other exemplary embodiments of the invention the concentratedback-extract is incorporated into extraction 120A where it optionallycontributes to sugar recovery (see FIG. 24). Optionally, incorporatingthe concentrated back-extract into the recycled HCl stream contributesto sugar recovery.

When back extraction is conducted in two stages (130 and 132), reducinga concentration of HCl in the back extractant in the second stage (132)contributes to an increase of efficiency of HCl extraction in thatsecond stage.

In some embodiments, a fraction of the dilute back-extract is treated inevaporation module 145 containing at least one low-pressure evaporator140 and at least one high-pressure evaporator 142 to generate asub-azeotropic acid condensate and (super-azeotropic) gaseous HCl andthe method includes incorporating the gaseous HCl into the recycled HClstream. Optionally, low-pressure evaporator 140 generates thesub-azeotropic dilute acid condensate. Optionally, high-pressureevaporator 142 generates the gaseous HCl.

In some embodiments, the lignin stream is washed with a fraction of thedilute back-extract from 132 (after passage through absorber 150; FIG.23) and/or with a fraction of the mixture from 111 (FIG. 24) to generatea washed lignin stream and a wash liquor containing sugars. In someembodiments, the washed lignin stream proceeds forward tode-acidification 164 and the wash liquor flows backwards so that it isincorporated into the recycled HCl stream arriving at hydrolysis 110.

In some embodiments, the solid lignin stream includes sugars, and thesolid lignin stream is washed with a fraction of dilute back-extractfrom 132. Optionally, the method includes absorbing HCl in the fractionof dilute back-extract from 132 prior to the washing. In someembodiments the method includes absorbing HCl (150) in at least aportion of the mixture from 111 prior to washing (see FIG. 24).

In some embodiments, the method includes contacting super-azeotropic HClwith a concentrated HCl stream to generate an HCl solution ofintermediate concentration and/or the method includes contactingsub-azeotropic HCl with a concentrated HCl stream to generate an HClsolution of intermediate concentration. In some embodiments, theconcentrated HCl stream is a gaseous stream (e.g. from 142 and/or from111) and the contacting includes absorption in a gas-liquid absorber(e.g. at 150). In some embodiments, the method includes contacting theevaporated mixture of water and HCl from said hydrolysate produced at111 with at least one other HCl stream. In some embodiments, the methodincludes washing 162 the solid lignin stream with the HCl solution ofintermediate concentration (e.g. from 150).

Additional Exemplary Method

Referring again to FIG. 23, some embodiments relate to a methodincluding hydrolyzing 110 a lignocellulosic material with a recycled HClstream containing wash liquor (optionally a lignin wash liquor). In someembodiments, hydrolysis 110 forms an aqueous hydrolysate and a solidlignin stream. Optionally, the hydrolysate includes a sugar mixture andHCl at more than 20%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%or 35% weight/weight HCl/[HCl and water] and/or the lignin streamcontains HCl more than 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%or 35% weight/weight HCl/[HCl and water] and sugars.

In some embodiments, the method includes extracting (120A and/or 120B)the hydrolysate with a recycled extractant (optionally de-acidified)including an S1 solvent. In some embodiments, extraction involves atleast two extraction steps (120A and 120B are depicted) to form anextract containing more than 20% or more than 25% weight/weight HCl/[HCland water]. In some embodiments, the extraction is conducted in a singleextraction step.

Optionally, the method includes increasing a monomeric sugar tooligomeric sugar ratio in the sugar mixture and polishing the sugarmixture to produce a polished mixture containing at least 70% monomericsugars out of total sugars and less than 1% weight/weight HCl (e.g. bysecondary hydrolysis 124 and/or by chromatography 128).

In some embodiments, the method includes back-extracting (130 and/or132) the extract with an aqueous solution to form a de-acidifiedextractant. In some embodiments, back-extraction involves at least twoback-extraction stages (130 and 132). Optionally, one of these backextractions is a concentrated stage (130) forming a concentratedback-extract and an HCl-depleted extract and the other is a dilute stage(132) forming a dilute back-extract and a de-acidified extractant.

In some embodiments, the method includes washing the solid lignin streamwith a lignin washing stream containing at least a fraction of theback-extract from 132 to produce a washed lignin stream and a washliquor. In some embodiments, the washing stream passes through absorber150 where the HCl concentration is increased by contact with gaseousHCl.

In some embodiments, the method includes de-acidifying 164 the washedlignin stream to form de-acidified washed lignin 165 and ade-acidification HCl stream (arrow from 164 to 140).

In some embodiments, the method includes evaporating an aqueous LP—HClsolution (i.e. feed to 140 from 132) in at least one low-pressureevaporator 140 to generate a sub-azeotropic dilute acid condensate and asuper-azeotropic aqueous HCl solution and evaporating an aqueous HP—HClsolution (i.e. feed to 142 from 140) in at least one high-pressureevaporator 142 to generate gaseous HCl and sub-azeotropic aqueous HClsolution. In some embodiments, the aqueous LP—HCl solution includes thesub-azeotropic HCl solution and/or dilute back-extract and/or thede-acidification HCl stream. In some embodiments, the aqueous HP—HClsolution includes the super-azeotropic HCl solution and/or thede-acidification HCl stream or the dilute back-extract. In someembodiments, concentrated back-extraction stage 130 employs thesuper-azeotropic solution from low-pressure evaporation 140 or thesub-azeotropic solution from high-pressure evaporation 142 as a backextractant. In some embodiments, the sub-azeotropic acid condensate fromlow-pressure evaporation 140 serves as a back extractant in the dilutestage 132 of the back-extracting.

In some embodiments, the method includes pre-evaporating 111 a mixtureof water and HCl from the hydrolysate prior to the extracting (120Aand/or 120B). Various possible uses of this mixture and/or their effectson energy consumption at evaporation module 145 are as describedhereinabove. In some embodiments, at least a portion of the mixture ofwater and HCl from evaporating 111 washes solid lignin (e.g. at 162and/or 160). In some embodiments, this washing occurs after the at leasta portion of the mixture passes through absorber 150.

In some embodiments, the lignin washing stream includes a fraction ofthe dilute back-extract from 132 and a fraction of said gaseous HClgenerated in high-pressure evaporation 142 (arrow from 150 to 162).

In some embodiments, the method includes contacting super-azeotropic HClwith a concentrated HCl stream to generate an HCl solution ofintermediate concentration. In some embodiments, the method includescontacting sub-azeotropic HCl with a concentrated HCl stream to generatean HCl solution of intermediate concentration. In some embodiments, theconcentrated HCl stream is a gaseous stream (e.g. from 142) and thecontacting includes absorption in a gas-liquid absorber (e.g. at 150).In some embodiments, the method includes contacting the evaporatedmixture of water and HCl from the hydrolysate (arrow from 111 to 150;FIG. 23 and/or to 142; FIG. 24) with at least one other HCl stream. Insome embodiments, washing the solid lignin stream (e.g. at 162) employsthe HCl solution of intermediate concentration (e.g. from 150).

Additional Exemplary Flow Paths

Referring now to FIG. 24, in some embodiments, streams of HCl/water aredelivered from low pressure evaporation unit 140 to back extraction 130and/or lignin-deacidification 164. In some embodiments, a stream ofHCl/water is delivered from low pressure evaporation unit 140 toabsorber 150 (e.g. by mixing with the stream from 111 as depicted).

Exemplary System

Referring again to FIG. 23, some embodiments of the present inventionprovides a system including an absorber 150 adapted to receive a flow ofgaseous HCl from an evaporation module 145, optionally fromhigh-pressure evaporation unit 142 and absorb the gaseous HCl into anaqueous solution to produce a concentrated HCl solution. In someembodiments, absorber 150 absorbs a mixture of HCl and water frompre-evaporation module 111.

In some embodiments, the system includes a lignin de-acidificationmodule (160+162+164) adapted to contact the concentrated HCl solution(from 150) with an acidic lignin stream in a countercurrent flow. Insome embodiments, the system includes a back extraction module (132and/or 130) adapted to provide the aqueous solution by back-extractingan S1 solvent extract of an acid hydrolysate of lignocellulosicmaterial. In some embodiments, the system includes an extraction module(120A and/or 120B) adapted to provide the S1 solvent extract to backextraction module (132 and/or 130). In some embodiments, the systemincludes a hydrolysis vessel 110 adapted to receive a lignocellulosicmaterial and output an acidic lignin stream and a hydrolysate containingsugars and HCl. In some embodiments, the system includes a solventrecycling loop (see dashed arrow from 132 to 120B, with or withoutpurification 135. In some embodiments, the system includes anevaporation module 145 including at least one low-pressure evaporationunit 140 and at least one high-pressure evaporation unit 142. In someembodiments, the system includes a pre-evaporation module 111 configuredto evaporate a mixture of water and HCl from the hydrolysate and deliverat least a portion of the mixture to absorber 150. In some embodiments,low-pressure evaporation unit 140 is adapted to produce a sub-azeotropicacid condensate and a super-azeotropic HCl solution from a back-extractprovided by back extraction module 132. In some embodiments,high-pressure evaporation unit 142 is adapted to produce the gaseous HCland a sub-azeotropic HCl solution.

Exemplary Evaporation Considerations

In some embodiments, low-pressure evaporation 140 is conducted at about50° C. and about 100 millibar (bottoms). In some embodiments,high-pressure evaporation 142 is conducted at about 135° C. and about 4bar (bottoms).

XII. Alternative Cellulose Sugar Refining Embodiments

FIG. 26 a is a schematic representation of an exemplary embodiment of asugar refining module indicated generally as 202. This specificationrefers to HCl as an exemplary acid, although other acids could beemployed. Reference is made specifically to HCl as an example in thissection. Other acids (e.g. sulfuric acid) can be used.

Module 202 is a system including a secondary hydrolysis unit 240 adaptedto receive an input stream 131 a including a sugar mixture in a superazeotropic HCl aqueous solution. and increase a ratio of monomericsugars to oligomeric sugars in an output stream 131 b and achromatography component 270 adapted to separate said output stream toproduce a monomer cut 230 enriched in monomeric sugars and an oligomercut 280 enriched in oligomeric sugars. In some embodiments, stream 131 aincludes at least 20% weight/weight sugar in an aqueous solution of HClIn some embodiments, oligomer cut 280 is recycled to secondaryhydrolysis unit 240. Optionally, this recycling contributes to areduction in acid and/or sugar concentration during hydrolysis.

In some embodiments, the separation of monomers from oligomers is notabsolute. In some embodiments, monomer cut 230 includes at least 65%,70%, 75%, 80%, 85%, 90%, 95%, 97.5% or 99% weight/weight (orintermediate or greater percentages) monomeric sugars as a percentage oftotal sugars. In other embodiments, oligomer cut 280 includes at least65%, 70%, 75%, 80%, 85%, 90%, 95%, 97.5% or 99% weight/weight (orintermediate or greater percentages) oligomeric sugars as a percentageof total sugars. In some embodiments, oligomer cut 280 includes residualacid.

In some embodiments, the system includes an acid extractor (twoextractors 210 a and 210 b are depicted) adapted to contact at least oneof input stream 130 and output stream 131 b or 131 c with an extractantcontaining an S1 solvent 155. In some embodiments, removal of acid byextraction contributes to a reduction in re-oligomerization of monomersand/or to a reduction in damage to resins and/or to an ability torecycle acid to main hydrolysis reactor 110 (FIG. 25). In someembodiments, the acid extractor includes at least two acid extractors210 a and 210 b arranged in series. In some exemplary embodiments, thearrangement is as depicted in the figure so that secondary hydrolysisreactor 240 is disposed between any pair of the at least two acidextractors (210 a and 210 b).

In some embodiments, the system includes a filtration unit 250positioned to filter output stream 131 b from secondary hydrolysis unit240. In some embodiments, the system includes an ion exchange component251 adapted to remove residual acid 156 from output stream 131 c or 133.In some embodiments, provision of acid extractor 210 b contributes to areduction in the amount of residual acid at 156. In some embodiments,the system includes an evaporation unit 260 disposed between secondaryhydrolysis unit 240 and chromatography component 270. Evaporation unit260 increases a total sugar concentration in stream 131 e enteringchromatography unit 270. Optionally, the higher concentration of sugarscontributes to an efficiency of separation of monomers from oligomers at270. In some embodiments, the system includes an evaporation unit (290;FIG. 26 c) disposed upstream of said secondary hydrolysis reactor. Unit290 is described in greater detail in the context of FIG. 26 c.

Module 202 can also be described as a system including an acid extractor210 (two extractors 210 a and 210 b are depicted in the drawing) and achromatography component 270. In some embodiments, chromatographycomponent 270 employs simulated moving bed (SMB) and/or sequentialsimulated moving bed (SSMB) technology. In some embodiments, 12 columnsoperating in an SSMB mode are used. In other exemplary embodiments ofthe invention, larger or smaller numbers of columns are employed. Insome embodiments, chromatography component functions to separate anoligomer cut 280 enriched in oligomeric sugars from a monomer cut 230enriched in monomeric sugars (enrichment here being relative to totalsugars).

Depicted exemplary acid extractors 210 a and 210 b are adapted toextract acid from an input stream 130 an input stream containing a sugarmixture in a super azeotropic HCl aqueous solution. In some embodiments,the sugar mixture includes at least 20%; at least 22%; at least 24%; atleast 26% or at least 28% weight/weight sugar in a super azeotropic HClaqueous solution. In some embodiments, the super azeotropic HCl aqueoussolution includes 22, 23, 24, 25, 26, 27, 28, 29, 30% weight/weight orintermediate or greater percentages of % HCl/[HCl and water]. Accordingto other exemplary embodiments of the invention the super azeotropic HClaqueous solution includes less than 40%, 38%, 36%, 34% or less than 32%weight/weight HCl/[HCl and water]. In some embodiments, adaptationincludes regulation of relative flow rates and/or extractant compositionand/or temperature conditions. In some embodiments, extraction is withan extractant including an S1 solvent (as defined hereinabove) toproduce an output sugar stream 131 a. In some embodiments, the S1solvent includes at least one of n-hexanol and 2-ethyl-hexanol. In someembodiments, the S1 solvent is hexanol and the extraction is conductedat a temperature of 45 to 55° C., optionally about 50° C. In FIG. 26 athe extractant is depicted as solvent 155 for clarity. In actualpractice, materials in addition to S1 solvent may be present in theextractant. In some embodiments, these additional materials result fromextractant recycling.

Chromatography component 270 is adapted to separate sugars from outputstream 131 a to produce an oligomer cut 280 enriched in oligomericsugars and a monomer cut 230 enriched in monomeric sugars. (relative toinput stream to chromatography component 270). In some embodiments,chromatography component 270 includes an ion exchange resin. Exemplaryadaptations include resin choice, flow rate and elution conditions.

In some embodiments, acid extractor (210+210 b) produces a countercurrent flow between input stream 130 and extractant including solvent155. At some point during the extraction, HCl 140 (dashed arrows) isseparated from stream 130 and begins to flow together with solvent 155(solid arrows) in the extractant. In some embodiments, the resultantS1/HCl liquid phase containing more than 20%, 22%, 24%, 26%, 28%, 30%,32%, 34%, 36%, 38% or 40% weight/weight [HCl/(HCl and water)].Optionally, the resultant S1/HCl liquid phase containing less than 50%,less than 48%, less than 46%, less than 44% or less than 42%weight/weight [HCl/(HCl and water)].

In some embodiments, the counter current flow is created by deliveringextractant containing solvent 155 from recovery module 150 to a bottomend of acid extractor 210 b while input stream 130 is delivered to a topend of acid extractor 210 a. In some embodiments, one or more pumps (notdepicted) deliver extractant containing solvent 155 and/or input stream130 to extractor(s) 210. In some embodiments, acid extractor 210includes at least one pulsed column. Optionally, the pulsed column is aBateman pulsed column (Bateman Litwin, Netherlands).

The Bateman pulsed column includes a large diameter vertical pipe filledwith alternating disc & doughnut shaped baffles which insure contactbetween descending stream 130 and ascending extractant 155 as they passthrough the column. The solvent in extractant 155 removes at least 35%,40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% or at least 92%weight/weight or intermediate or greater percentages of acid 140 fromstream 130.

In some embodiments, sugars exit extractor(s) 210 in an acid depletedstream 131 a and enter secondary hydrolysis module 240.

The various exemplary embodiments of the invention deal with both sugarrefining, and considerations relating to recycling of HCl and/orsolvent. In order to prevent confusion, the following description willfollow sugar stream 130 as it proceeds through module 202 to emerge asmonomer cut 230. In some embodiments, monomer cut 230 is substantiallyfree of acid (e.g. less than 0.1 or less than 0.05% on as is basis.). Inother embodiments, monomer cut 230 includes less than 0.9%, 0.8%, 0.7%,0.6%, 0.5%, 0.4%, 0.3%, 0.2% or even less than 0.1% weight/weight HCl onas is basis.

Returning now to a sequential description of input sugar stream 130 asit moves through module 202: stream 130 flows through extractor 210(depicted here as 210 a and 210 b) and is extracted with an extractantincluding both an S1 solvent 155 and HCl 140. In some embodiments,stream 130 includes at least 20% total sugars and a super azeotropicconcentration of HCl in an aqueous solution prior to extraction at 210a. These total sugars may include as much as 30, 40, 50, 60 or even 70%(weight basis) oligosaccharides or intermediate or greater percentages.

In some embodiments, the sugars emerge from extractors 210 a and 210 bas an acid reduced stream 131 a. Optionally, extraction at 210 removeswater and/or HCl so that sugar concentration at 131 a is higher than at130. The ratio of monomeric sugars to oligomeric sugars remainssubstantially unchanged at this stage. The HCl concentration has beenreduced by extraction at 210. HCl 140 and S1 solvent 155 exit extractor210 a to recovery module 150. In some embodiments, HCl 140 and S1solvent 155 are subjected to distillation. Recovery module 150 recyclesseparated HCl (dashed arrow) to hydrolysis reactor 110 and sendsseparated solvent 155 to extractor 210 b. In some embodiments, recoverymodule 150 employs back extraction as described in section XI.

In some embodiments, acid reduced stream 131 a flows to secondaryhydrolysis reactor 240 where it is optionally mixed with an oligomer cut280 (finely dashed arrow) from chromatography unit 270. In someembodiments, hydrolysis reactor 240 is disposed between acidextractor(s) 210 and chromatography component 270.

Since oligomer cut 280 is more dilute with respect to both total sugarsand HCl than stream 131 a, this mixing serves to reduce the sugarconcentration (and HCl concentration) in secondary hydrolysis 240.Optionally, additional aqueous streams are added at this stage tofurther reduce the total sugar concentration and/or to reduce the acidconcentration and/or to increase the proportion of oligomeric sugars.Optionally, reduction of sugar concentration contributes to a lowerequilibrium concentration of oligomers.

For example, oligomer cut 280 caries additional sugars, primarilyoligomeric sugars. The effect of this mixing is that the HClconcentration is reduced to 1.0%, 0.9%, 0.8%, 0.7%, 0.65, 0.5%weight/weight or less on as is basis. Optionally, the HCl concentrationis reduced to between 0.3% to 1.5%, between 0.4%-1.2% or between0.45%-0.9% weight/weight. In some embodiments, the total sugarconcentration at 240 is reduced to below 25%, below 22%, below 19%,below 16%, below 13% or even below 10% weight/weight. In someembodiments, oligomer cut 280 functions as an oligomeric sugar returnloop.

Following this mixing, the resultant sugar solution in dilute HCl issubject to a secondary hydrolysis reaction in module 240. In someembodiments, this secondary hydrolysis continues for at least 1, atleast 2 or at least 3 hours or intermediate or longer times. Optionally,this secondary hydrolysis lasts 1 to 3 hours, optionally about 2 hours.In some embodiments, the temperature is maintained below 150, 140, 130,120, 110, 100 or below 90° C. or intermediate or lower temperatures. Insome embodiments, the temperature is maintained between 60° C. to 150°C., between 70° C. to 140° C. or between 80° C. to 130° C. In someembodiments, the secondary hydrolysis conducted in module 240 results inmonomeric sugars proportion of 80 to 90%, optionally 85 to 88%,optionally about 86% of the total sugars In some embodiments, thesecondary hydrolysis conducted in module 240 results in monomeric sugarsproportion of at least 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88% oreven at least 90% weight/weight of the total sugars. In someembodiments, the resultant secondary hydrolysate 131 b contains at least20%, 22, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%or 50% weight/weight total sugars.

Although a single secondary hydrolysis reactor 240 is depicted betweenthe acid extractor (210 a and 210 b) and chromatography component 270for simplicity, one or more hydrolysis reactors 240 can be provided.

In some embodiments, hydrolysis reactor(s) 240 operate at 95, 100, 105,110, 115, 120 or 125° C. or intermediate or lower temperatures. In someembodiments, hydrolysis reactor(s) 240 operate at a pressure of 1.8,1.9, 2.0, 2.1 or 2.2 bar. In some embodiments, the hydrolysis reactioncontinues for 1 to 3 hours, 1.5 to 2.5 hours or 1.7 to 2 hours. In someembodiments, the hydrolysis reaction at 240 is conducted at 95° C. forabout 2 hours at atmospheric pressure. In other exemplary embodiments ofthe invention, the hydrolysis reaction at 240 is conducted at 125° C.for about 1.7 hours at about 2 bar.

In some embodiments, the resultant secondary hydrolysate 131 b leavesmodule 240 and proceeds to filtration unit 250. In some embodiments,filtration unit 250 is positioned to filter an exit stream fromsecondary hydrolysis reactor 240. In some embodiments, filtration unit250 removes fine particles from secondary hydrolysate 131 b. In someembodiments, these particles are periodically washed off the filter andsent back to extractor(s) 210, optionally using a mixture of acid (e.g.HCl), S1 solvent and water. In some embodiments, filtration unit 250includes microfiltration components. In some embodiments, filteredsecondary hydrolysate 131 c proceeds to anion exchanger 251 disposedbetween secondary hydrolysis reactor 240 and chromatography component270.

In some embodiments, anion exchanger 251 includes weak base anionexchange resin (WBA) and/or an amine including at least 20 carbon atoms.In some embodiments, anion exchanger 251 separates residual acid (e.g.HCl) 156 from stream 131 c. Stream 156 contains, according toalternative embodiments, the acid, its salt or a combination thereof. Insome embodiments, the anion exchanger at 251 is an amine and the salt in156 includes amine chloride. In some embodiments, use of an amine as ananion exchanger at 251 contributes to removal of color of from sugarsand/or contributes to a reduction in downstream sugar polishing.

In some embodiments, regenerating the anion exchanger is by treating theHCl-loaded anion exchanger with a base. In some embodiments, the baseselected from hydroxides, bicarbonates and carbonates of alkali metalsand ammonia. In some embodiments, the regeneration forms a chloride saltof the alkali metals or ammonia and the salt is treated to reform HCland the base. In some embodiments, the base is an ammonium base andammonium chloride is formed and is used at least partially as afertilizer.

Optionally, residual HCl or salt 156 is discarded as waste. In someembodiments, greater than 80, 82, 84, 86, 88, 90, 92, 94, 96 or greaterthan, 98% weight/weight of HCl entering anion exchanger 251 exits instream 156. In some embodiments, in some embodiments the HClconcentration in stream 132 is less than 2.5%, 2%, 1.5%, 1.0%, 0.5%,0.3%, 0.2%, 0.1%, less than 0.05% or less than 0.01% weight/weight on asis basis.

In some embodiments, anion exchanger 251 includes an amine and operatesat temperature(s) of 40 to 60° C., optionally about 50° C. In someembodiments, stream 132 which exits anion exchanger 251 proceeds to acation exchanger module 253. In some embodiments, cation exchangermodule 253 separates divalent cations (e.g. Mg++ and/or Ca++) from thesugar stream. In some embodiments, sugars 131 d are eluted separatelyfrom a divalent cation stream 157. In some embodiments, anion exchanger251 and/or cation exchanger module 253 dilute the concentration of totalsugars in stream 131 d which exits cation exchanger module 253. In someembodiments, sugar stream 131 d is concentrated by evaporation unit 260.In some embodiments, evaporation unit 260 is positioned between anionexchanger 251 and chromatography component 270. In some embodiments,evaporation unit 260 operates at a temperature of 60, 70, 80 or 90° C.or intermediate or higher temperatures. In some embodiments, evaporationunit 260 operates at a pressure of 150, 250, 350, 450, 550, 650, 750,850 or 950 mbar or intermediate or greater pressures. In someembodiments, temperature and/or pressure conditions vary in a controlledmanner in evaporation unit 260 during evaporation. Optionally, contentsof unit 260 are divided into portions and each portion is evaporatedunder different conditions. In some embodiments, heat from a previousportion evaporates a next portion.

Evaporation unit 260 removes water 142 from stream 131 d. Optionally, atleast a portion of water 142 from evaporation unit 260 serves as aneluent for chromatography component 270 and/or as a diluent at secondaryhydrolysis module 240. Evaporation of water causes sugar concentrationto increase. This increase in sugar concentration can contribute tooligomerization (re-oligomerization) of sugars, especially if HCl ispresent. In some embodiments, removal of HCl 140 and/or 156 contributesto a reduction in the re-oligomerization. Exemplary ways to reduce suchre-oligomerization are discussed in “Exemplary equilibriumconsiderations” of this section.

Concentrated filtered secondary hydrolysate 131 e leaves evaporationunit 260 with at least 32%, optionally at least 35% weight/weightsugars. In some embodiment, 131 d leaves evaporation unit 260 withbetween 40% to 75%, between 45% to 60% or between 48% to 68%weight/weight sugars. In some embodiments, an increase in sugarconcentration contributes to an increase in efficiency ofchromatographic separation.

In some embodiments, concentrated filtered secondary hydrolysate 131 eleaves evaporation unit 260 with at least 30, 40, 50 or 60%weight/weight or greater percentages of total sugars. Concentratedfiltered secondary hydrolysate 131 e proceeds to chromatographycomponent 270, which optionally includes an ion exchange resin.Concentrated filtered secondary hydrolysate 131 e includes a lowerconcentration of acid than hydrolysate 131 c due to removal of HCl 156at 251. In some embodiments, concentrated filtered hydrolysate 131 eincludes less than 1%, less than 0.9%, less than 0.8%, 0.7%, 0.6%, 0.5%,0.4%, 0.3%, 0.2%, 0.1% or 0.05% weight/weight HCl on as is basis.“Exemplary equilibrium considerations” is described in this section.

Stream 131 e is fed onto the chromatography resin and eluted using anaqueous solution. In some embodiments, aqueous solution 142 deliveredfrom evaporator 260 can serve as an eluting stream. This elutionproduces an oligomer cut 280 (fine dashed arrows to secondary hydrolysismodule 240) and a monomer cut 230.

Chromatographic separation 270 includes contacting with the sugarmixture and with eluting stream. The eluting stream is water or anaqueous solution. In some embodiments, the aqueous solution is formed inanother stage of the process. In some embodiments, an aqueous stream ofhemicellulose sugars is used. Optionally, the aqueous stream ofhemicellulose sugars is a product of pretreating lignocellulosicmaterial with hot water. Exemplary methods for pretreatinglignocellulosic material with hot water are described inPCT/US2012/064541 (incorporated herein by reference for all purposes).

In some embodiments, a cation exchange resin is employed forchromatographic separation 270. According to some embodiments, the resinis loaded at least partially with cations of alkaline metals orammonium.

In some embodiments, monomer cut 230 contains 80%, 85%, 90%, 95% or97.5% weight/weight or intermediate or greater percentages of the sugarswhich were originally present in mixture 130. In some embodiments, thesesugars are about 80 to 98%, optionally about 89 to 90% monomeric sugarsand about 2 to 20%, optionally about 10 to 11% weight/weight oligomericsugars. In some embodiments, these sugars are at least 80%, at least 82,at least 84%, at least 86%, at least 88%, at least 90%, at least 92%, atleast 94%, at least 96, at least 98% weight/weight or intermediate orgreater percentages monomeric sugars out of total sugars. In someembodiments, monomer cut 230 contains at least 20%, at least 22, atleast 24%, at least 26%, at least 28%, at least 30%, at least 32%, atleast 34%, at least 36%, at least 38%, at least 40%, at least 42%, atleast 44%, at least 46%, at least 48% or at least 50% weight/weighttotal sugars. Any sugars that remain in the oligomer cut can berecovered to a great extent in subsequent rounds of recycling. In someembodiments, sugars that remain in the oligomer cut can be convertedfrom an oligomer rich mixture to a mixture that is primarily monomericsugars.

Although the refining process has been described as a linear progressionfor the sake of clarity, in practice it can be both continuous and/orcyclical in part.

Optional Additional Refining Components

FIG. 26 b depicts additional optional components of module 200 depictedgenerally as module 204. Optional module 204 further refines output 230of module 202. Depicted exemplary module 204 includes a desolventizer272 adapted to remove any remaining residual solvent 155 from monomercut 230. This solvent can be recovered by sending it to recovery module150, or to extraction unit 210 (210 a is indicated in the drawing). Thesugars continue to purification media 274 adapted to remove impuritieslikely to adversely affect downstream fermentation. In some embodiments,purification media 274 includes granular carbon, optionally provided ina column. Optionally, the granular carbon removes impurities includingcolor bodies, color precursors, hydroxymethylfurfural, nitrogencompounds, furfural, and proteinaceous materials. Each of thesematerials has the potential to inhibit fermentation.

In some embodiments, purification media 274 includes an ion exchangeresin. In some embodiments, ion exchange resin removes any anions and/orcations. In some embodiments, these anions and/or cations include aminoacids, organic acids and mineral acids. Optionally, the ion exchangeresin includes a combination of strong acid cation resin and weak baseanion resins.

In some embodiments, purification media 274 polishes the sugars with amixed bed system using a combination of strong cation resin and strongbase anion resin. In some embodiments, the sugars concentration at thisstage is about 34 to 36%. In some embodiments, a concentrator 276adapted to increase a solids content of monomer cut 230 is employed.Concentrator 276 optionally evaporates water. In some embodiments,resultant refined sugar output 230′ is a solution of 77 to 80% sugarwith 70% or more, 80% or more, 90% or 95% weight/weight or more of thesugars present as monomers.

In some embodiments, a resultant product (e.g. resulting from 230)includes at least 50%, 60%, 65%, 70% or 75% weight/weight sugar. In someembodiments, the resultant product includes at least 92%, 94%, 96%, 97%or 98% weight/weight monomeric sugars relative to total sugars. In someembodiments, the resultant product includes less than 0.3%, 0.2%, 0.1%or 0.05% weight/weight HCl on as is basis.

Exemplary Optional Pre-Evaporation Module

FIG. 26 c depicts additional optional components of module 200 depictedgenerally as module 205. In those embodiments which include it, optionalmodule 205 is positioned upstream of extractor 210 a (FIG. 26 a). Insome embodiments, input stream 130 (as described above) enterspre-evaporation module 290. Pre-evaporation optionally includesdistillation and/or application of vacuum pressure. Pre-evaporation inmodule 290 produces a gaseous mixture 292 of HCl and water and amodified input stream 131 g. In some embodiments, modified input stream131 g has a higher sugar concentration and a lower HCl concentrationthan input stream 130. For example, in some embodiments, module 290increases the sugar concentration in the stream from 25% to 30%weight/weight. In some embodiments, module 290 decreases the HClconcentration from 33% to 27% weight/weight [HCl/(HCl and water)].

In some embodiments, module 290 operates at a temperature of 50 to 70°C., optionally about 55 to 60° C. In some embodiments, module 290operates at a pressure of 100 to 200 mbar, optionally 120 to 180 mbar,optionally about 150 mbar. In some embodiments, evaporation at 290produces a vapor phase with a higher HCl concentration than in feedstream 130. According to those embodiments, pre-evaporation at 290decreases HCl concentration by at least 2%, 4%, 6%, 8%, 10%, 12%, 14% or16% weight/weight relative to its concentration in 130. In someembodiments, pre-evaporation at 290 increases total sugar concentrationby at least 2%, 4%, 6%, 8%, 10%, 12%, 14% or 16% weight/weight relativeto its concentration in 130.

In some embodiments, the HCl concentration in the vapor phase from 290is greater than 30, 35, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58 or 60%weight/weight or intermediate or greater percentages [HCl/(HCl andwater)].

According to those embodiments of the invention that includepre-evaporation module 290, stream 131 g replaces 130 as an input streamfor extractor 210 a in FIG. 26 a.

Exemplary Considerations in Use of an Amine Extractant as an AnionExchanger

FIG. 26 d depicts a de-acidification system similar to that of FIG. 26 awith optional additional or alternative components indicated generallyas 206. Numbers in FIG. 26 d which are used also in FIG. 26 a indicatelike components or streams. Some items depicted in FIG. 26 a andexplained hereinabove are not depicted in FIG. 26 d for clarity. Thedepicted exemplary configuration 206 is suitable for embodiments of theinvention which employ an amine extractant at anion exchange 251.

In some embodiments, filtered secondary hydrolysate 131 c contains 6 to16%, 7 to 15%, 8 to 14%, 9 to 13% or 10 to 12% weight/weight sugars. Insome embodiments, filtered secondary hydrolysate 131 c contains lessthan 1.2%, 1.1%, 1.0%, 0.9%, 0.8% or 0.7% weight/weight HCl on an as isbasis. In some embodiments, filtered secondary hydrolysate 131 ccontains more than 0.2%, 0.3%, 0.4% or 0.5% weight/weight HCl on an asis basis.

In some embodiments, the amine at 251 is provided as part of anextractant. For example, in some embodiments the extractant includes 40to 70%, 45 to 65%, 48 to 60% or 50 to 55% amine by weight and alsoincludes a diluent. Amines suitable for use in the extractant at 251include tri-laurylamine (TLA; e.g. COGNIS ALAMINE 304 from CognisCorporation; Tucson Ariz.; USA), tri-octylamine, tri-caprylylamine andtri-decylamine. All these are tertiary amines. In other exemplaryembodiments of the invention, secondary and primary amines with at least20 carbon atoms are employed. Diluents suitable for use in theextractant at 251 include long chain alcohols (e.g. hexanol and/ordodecanol). In some embodiments, the diluent contains additionalcomponents.

In some embodiments, an organic:aqueous phase ratio of the amineextractant (relative to the 131 c aqueous phase) at 251 is between 1:1to 1:4; between 1:1.2 to 1:3.5; between 1:1.4 to 1:3.0, optionally about1:2. In some embodiments, the extraction with an amine at 251 occurs in4 or less, 3 or less, 2 or less, or 1 stage(s). In some embodiments,each stage occurs in a mixer settler. In some embodiments, mixing in agiven stage continues for less than 10 minutes, 8 minutes, 6 minutes, 4minutes or 2 minutes or intermediate or shorter times. In someembodiments, in some embodiments settling in a given stage continues forless than 10 minutes, 8 minutes, 6 minutes, 4 minutes, 2 minutes or 1minute or intermediate or shorter times. In some embodiments, theextraction with an amine at 251 occurs at 40° C. to 80° C.; 45° C. to75° C.; 50° C. to 70° C. or about 60° C.

In some embodiments, sugar stream 132 (e.g. 132 a in FIG. 26 d) exiting251 contains less than 1000 ppm, less than 800 ppm, less than 700 ppm,less than 600 ppm, less than 500 ppm, less than 400 ppm, less than 300ppm, less than 200 ppm or less than 100 ppm HCl or intermediate or loweramounts of HCl. In some embodiments, sugar stream 132 (e.g. 132 a inFIG. 26 d) exiting 251 contains more than 20 ppm, more than 40 ppm, morethan 60 ppm or more than 80 ppm or intermediate or greater amounts ofHCl.

In some embodiments, extract 156 contains amine chloride. In someembodiments, extract 156 includes residual sugars. Optionally, thesesugars are recovered by washing with water.

In some embodiments, sugar stream (raffinate) 132 a exiting amineextraction 251 contains only small amounts of amine due to the lowsolubility of amine (e.g. TLA) in aqueous solution. Optionally,raffinate 132 a is concentrated to about 40% to 80% (or saturation);about 45% to 75% (or saturation) or about 50% to 70%, optionally about60% weight/weight sugars (evaporator 260) and/or treated on a cationexchanger 253 prior to chromatographic separation 270. In someembodiments, cation exchanger 253 removes amine (e.g. TLA) fromraffinate 132 b in stream 157.

In some embodiments, an optional stripping unit 252 evaporates residualhexanol 133 (used as a diluent at 251) from raffinate 132 a. In someembodiments, recovered hexanol 133 is used in extraction 210 b asdepicted. In other exemplary embodiments of the invention, recoveredhexanol 133 is used as part of the diluent in the extractant at 251 (notdepicted). Hexanol depleted raffinate 132 b proceeds to cation exchanger253 and/or evaporation 260. Evaporation 260 increases the concentrationof sugars to about 60 sugars % and/or removes any remaining hexanol.

Exemplary Amine Recovery by Back Extraction

Referring still to FIG. 26 d, extraction with amine at 251 produces anextract 156 including a chloride salt of the amine. In some embodiments,back extraction 255 produces regenerated amine 258, and salts 256. Backextraction 255 employs a base 257 (e.g. Na2CO3; NH3 or NaOH). In someembodiments, Na2CO3 serves as base 257 and CO2 249 is produced. In otherexemplary embodiments of the invention, NaOH serves as base 257 and NaOHis regenerated by water splitting electro-dialysis of salts 256 (NaCl).Contacting of an aqueous basic solution (base 257 diluted with arecycled portion salts 256 (indicated as 256 r) with extract 156transforms amine chloride to regenerated amine 258 and a chloride salt(e.g. NaCl; 256). If Na2CO3 serves as the base, CO2 249 is alsoproduced. Since the amine (e.g. TLA) is immiscible with water,regenerated amine 258 separates from the aqueous phase in backextraction 255 and can be easily returned to anion exchange 251 foranother round of amine extraction. Excess salts 256 are removed as aproduct stream 256 p.

In some embodiments, salts 256 are recovered from back extraction 255 asan NaCl solution of 10%, 12%, 14%, 16%, 18% or 20% weight/weight orintermediate or greater percentages. In some embodiments, backextraction 255 contacts extract 156 with a recycled 20% NaCl solution(from 256 as indicated by dashed arrow) into which base 257 (e.g.Na2CO3) is added. Back extraction 255 produces regenerated amine 258 andsalts 256. In some embodiments, a portion of salts 256 is re-cycled toback extraction 255. Remaining salts 256 are optionally removed as aproduct stream. In some embodiments, the ratio of organic phase:aqueousphase at 255 is between 7:1 to 1:1; between 6:1 to 2:1; between 5:1 to3:1 or between 4.5:1 to 3.5:1. In some embodiments, back extraction 255is conducted in a single step.

In some embodiments, the organic phase including regenerated amine 258includes <0.3%; <0.25%; <0.2%; <0.15%; <0.1% or <0.05% weight/weight HClon as is basis.

In some embodiments, the amount of base 257 (e.g. Na2CO3) isstoichiometric or 10%, 15%, 20%, 25% or 30% weight/weight abovestoichiometric or intermediate or lower percentages above stoichiometricrelative to HCl in 156 For example, if stream 156 also includesextracted carboxylic acids, the base used should be in an amountsufficient to transfer both chloride ions and the carboxylic acids totheir salt form. In some embodiments, this results in regeneration ofthe amine. In some embodiments, back-extraction 255 is conducted at 60to 100° C.; 65 to 95° C.; 70 to 90° C. or 75 to 85° C.

In some embodiments, the organic phase including regenerated amine 258is washed with an aqueous solution to remove residual salts (e.g. NaCl,and/or organic acid salts) prior to return to 251 (not depicted).

Exemplary Diluent Considerations

In some embodiments, stream 131 c entering amine extraction 251 (to beextracted by the amine) contains residual hexanol 155 from theextraction 210 a and/or 210 b. For example, the amount of residualhexanol is 0.05%; 0.1%; 0.2%; 0.3%; 0.4% or 0.5% or intermediate amountsin various exemplary embodiments of the invention. As described above,amine extraction at 251 employs an extractant including amine anddiluent. In some embodiments, diluent component of the extractantincludes hexanol. In some embodiments, the hexanol concentration (aspart of the diluent of the extractant at 251) is 35%, 40%, 45%, 50% 55%or 60% or intermediate or lesser percentages relative to totalextractant at 251. According to these embodiments, both raffinate 132 afrom amine extraction 251 and extract 156 (and the salt product 256)contain small amounts of hexanol. For example, raffinate 132 a contains0.3%, 0.4%, 0.5% or 0.6% hexanol in various exemplary embodiments of theinvention.

In some embodiments, salts 256 contain 0.10%, 0.14%, 0.18%, 0.22%,0.26%, 0.38% in various exemplary embodiments of the invention. Inexemplary embodiments, both raffinate 132 a and salts 256 areconcentrated and hexanol 133 in raffinate 132 a is distilled out atstripper 252.

In some embodiments, hexanol concentration in the extractant ismaintained at a desired level (e.g. 44%) by providing “make-up” hexanolprior to a next amine extraction cycle at 251. The amount of make-uphexanol is, for example, about 1.5% relative to the desired level ofhexanol in the extractant. In some embodiments, make-up hexanol isprovided by distillation of hexanol 133 from raffinate 132 a anddelivery of hexanol 133 to amine extraction 251. In some embodiments,the organic phase including regenerated amine 258 is washed with anaqueous solution including condensed hexanol 133 to combine the wash ofresidual salts and hexanol re-introduction.

In other exemplary embodiments of the invention, the diluent of theamine extractant (e.g. TLA) includes kerosene and/or an alcohol of achain length greater than 10, e.g. C12, C14 or C16 as a primarycomponent. According to these embodiments, hexanol from stream 131 caccumulates in the amine extractant. In some embodiments, accumulatedhexanol in the amine extractant is removed by distillation.

Exemplary Carboxylic Acid Considerations

In some embodiments, sugar stream 131 c contains anions of carboxylicacids resulting from hydrolysis 110 (FIG. 25). For example, thesecarboxylic acids include acetic acid and/or formic acid in variousembodiments of the invention.

In some embodiments, a number of equivalents of protons in sugarsolution 131 c is smaller than the number of equivalents of anions(including chloride). In some embodiments, solution 131 c is treated ona cation exchanger 253′ in acid form prior to amine extraction 251. Insome embodiments, cation exchanger 253′ converts anions in solution 131c to their acid form. In some embodiments, cation exchanger 253′ removesorganic impurities and/or contributes to an improvement in phase contactand/or phase separation in amine extraction 251.

In some embodiments, amine extraction 251 removes HCl and/or organicacids from sugars in stream 131 c. In some embodiments, such removalcontributes to a decrease in load on polishing components locateddownstream. In some embodiments, 60%, 65%, 70%, 75%, 80%, 85%, 90% or95% weight/weight or intermediate or greater percentages of organicacids are removed by amine extraction 251.

In some embodiments, back-extraction 255 with base (e.g. Na2CO3) isdivided into two stages. In the first stage, the amount of Na2CO3 isequivalent to that of carboxylic acid and only the carboxylic acids areback-extracted to produce a solution of their (e.g. sodium) salt(s). Inthe second stage, HCl is back-extracted. In that case, the first stageis done with a base, but not with a recycled NaCl solution. The secondstage uses recycled NaCl as described hereinabove.

These carboxylic acid considerations also apply to HCl removal when aweak-base anion-exchange resin is employed at 251. Such a weak-baseanion-exchange resin also adsorbs carboxylic acids after thecation-exchanger treatment 253′.

First Exemplary Method

FIG. 27 is a simplified flow diagram of a method according to anexemplary embodiment of the invention depicted generally as 300. Method300 includes extracting 320 a sugar mixture 310 in a super azeotropicHCl aqueous solution with an extractant including an S1 solvent. In someembodiments, the super azeotropic HCl solution includes aqueous solutionof 22, 23, 24, 25, 26, 27, 28, 29, 30% weight/weight or intermediate orgreater percentages of % HCl/[HCl and water]. In some embodiments, thesuper azeotropic HCl solution includes 40, 38, 36, 34 or 32%weight/weight or intermediate or lower percentages of % HCl/[HCl andwater].

In some embodiments, method 300 includes separating 322 an S1/HCl liquidphase 324 containing more than 20, 22, 24, 26, 28, 30, 32, 34, 36, 38or, 40% weight/weight HCl/[HCl and water] and/or less than 50, 48, 46,44 or 42% weight/weight HCl/[HCl and water] from the sugar mixture.Optionally, method 300 includes separating the S1 from the HCl, forexample by distillation and/or back extraction. In some embodiments,this separation is conducted concurrently with washing of lignin stream120 (FIG. 25) as described in section XI above and in co-pendingapplication WO/2011/151823 (incorporated herein by reference for allpurposes).

In some embodiments, sugar mixture 310 includes hydrolysate 130 (FIG. 25or 26 a) and/or an acidic stream received from washing of the S1extractant from the extract. Optionally, washing of the S1 extractantfrom the extract includes back extraction.

In some embodiments, the method includes contacting 330 a resultantaqueous phase with an anion exchanger and separating 332 an HCl-loadedanion exchanger 334 from the sugar mixture.

Depicted exemplary method 300 includes increasing 340 a monomeric sugarto oligomeric sugar ratio (of sugars from the mixture) to produce amonomeric sugar enriched mixture 342 containing at least 70, 75, 80, 85,90, 95, 96, 97.5 or even 99% weight/weight or intermediate or greaterpercentages of monomeric sugars (relative to total sugars) by weight. Insome embodiments, this increase may be achieved by secondary hydrolysis(see 240 in FIG. 26 a) and/or chromatographic separation (see 270 inFIG. 26 a). In some embodiments, a combination of these techniques isemployed. Thus, increasing 340 can occur after separation 322 and/orafter separation 332 as depicted.

In some embodiments, increasing 340 includes performing chromatographicseparation (see 270 in FIG. 26 a). In some embodiments, a feed tochromatographic separation 270 includes less than 1.0, 0.9, 0.7, 0.5,0.3 or 0.1% weight/weight or intermediate or lower percentages HCl onHCl/(HCl and water) basis. In some embodiments, chromatographicseparation 270 includes employing a cation exchange resin for theseparation. In some embodiments, the cation exchange resin is at leastpartially loaded with cations of alkaline metals (e.g. sodium orpotassium) and/or ammonium. In some embodiments, chromatographicseparation 270 includes contacting the resin with the sugar mixture andwith an eluting stream. In some embodiments, the eluting stream is wateror an aqueous solution. In some embodiments, the aqueous solution isformed in another stage of the process. In some embodiments, the aqueousstream includes hemicellulose sugars. Optionally, a stream containinghemicellulose sugars results from pre-treating substrate 112 (FIG. 25)with hot water. Exemplary hot water treatments of substrate 112 aredisclosed in co-pending application PCT/US2012/064541 (incorporatedherein by reference for all purposes). In those embodiments which employa cation exchange resin, elution includes contacting with an aqueoussolution including hemicellulose sugars in some cases.

In those embodiments of the invention in which increasing 340 includeschromatographic separation (see 270 in FIG. 26 a) the monomeric sugar tooligomeric sugar ratio is increased to 80, 82, 84, 84, 86, 88, 90, 92,94, 96 or 98% weight/weight or intermediate or grater percentages.

In some embodiments, hydrolyzing occurs between extracting 320 andcontacting 330 (see 240 in FIG. 26 a). In some embodiments, increasing340 by hydrolyzing 240 increases the monomeric sugar to oligomeric sugarratio to 72, 74, 76, 78, 80, 82, 88 or 90% weight/weight or intermediateor greater percentages.

In some embodiments, the chromatographic separation (see 270 in FIG. 26a) produces an oligomer cut (280; FIG. 26 a) enriched in oligomericsugars relative to sugar mixture 310 and a monomer cut (230; FIG. 26 a)enriched in monomeric sugars relative to sugar mixture 310 on a weightbasis. In those embodiments of the invention which do not includecontact 330 with an anion exchanger monomeric sugar enriched mixture mayinclude residual HCl.

In those exemplary embodiments of the invention in which increasing 340includes both secondary hydrolysis 240 and chromatographic separation270, the ratio of monomeric sugars to oligomeric sugars in monomericsugar enriched mixture 342 (e.g. monomer cut 230 in FIG. 26 a) is 72,74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96 or 98% weight/weight orintermediate or greater percentages.

In some embodiments, extracting 320 of sugar mixture 310 concludes priorto beginning increasing 340 a monomeric sugar to oligomeric sugar ratioin the mixture as depicted in FIG. 27. In many embodiments of theinvention extracting 320 is less than 100% efficient so that the mixturestill contains HCl after extracting 320 is concluded. In other exemplaryembodiments of the invention, increasing 340 includes hydrolyzing (e.g.240 in FIG. 26 a) oligomeric sugars to monomeric sugars prior tobeginning extracting 320 sugar mixture 310 (not depicted in FIG. 27).This option is depicted in FIG. 26 a if stream 130 proceeds directly to240.

In some embodiments, hydrolyzing occurs between separating 322 andcontacting 330 (see 240 in FIG. 26 a). In some embodiments, thechromatographic separation (see 270 in FIG. 26 a) produces an oligomercut (280; FIG. 26 a) enriched in oligomeric sugars relative to sugarmixture 310 and a monomer cut (230; FIG. 26 a) enriched in monomericsugars relative to sugar mixture 310 on a weight basis.

Depicted exemplary method 300 includes separating 322 an S1/HCl liquidphase 324 from mixture 310 (e.g. by extraction 320). In someembodiments, S1/HCl liquid phase 324 includes more than 20, 25, 30, 35or even more than 40% HCl/[HCl and water]. In some embodiments, S1/HClliquid phase 324 includes less than 50, 48, 46, 44 or 42% weight/weightHCl/[HCl and water].

In some embodiments, the S1 solvent includes n-hexanol or2-ethyl-hexanol. Optionally, one of these two solvents is combined withanother S1 solvent. In some embodiments, the S1 solvent consistsessentially of n-hexanol. In some embodiments, the S1 solvent consistsessentially of 2-ethyl-hexanol. Optionally, the S1 solvent includesanother alcohol and/or one or more ketones and/or one or more aldehydeshaving at least 5 carbon atoms. In some embodiments, the S1 solvent hasa boiling point at 1 atm between 100° C. and 200° C. and forms aheterogeneous azeotrope with water, which azeotrope has a boiling pointat 1 atm of less than 100° C.

In some embodiments, extracting 320 includes counter current extraction.In some embodiments, extraction 320 serves to reduce the HClconcentration to less than 10%, 5%, 2.5% or 1% weight/weight orintermediate or lower percentages. In some embodiments, the monomericsugar enriched mixture 342 contains at least 20, 22, 24, 26, 28, 30, 32,34, 36, 38, 40, 42, 44, 46, 48 or 50% weight/weight or intermediate orgreater percentages of total sugars. In some embodiments, thisconcentration is higher than in mixture 310.

In some embodiments, monomeric sugar enriched mixture 342 includes lessthan 25, 20, 15 or 10% or 5%, 3% weight/weight or less oligomeric sugars(i.e. dimers or higher oligomers) out of the total sugars. In someembodiments, the anion exchanger at contacting 330 is a weak base resin(WBA). Optionally, regeneration 335 of WBA is by contact with a base. Insome embodiments, the base includes a hydroxide and/or a bicarbonateand/or a carbonate of one or more alkali metals and/or ammonia. In someembodiments, regeneration 335 forms a chloride salt of the alkalimetal(s) and/or ammonia and the salt is treated to reform HCl and thebase. In some embodiments, the base is an ammonium base and ammoniumchloride is formed as the salt. Optionally, formation of ammoniumchloride adds value to the process because ammonium chloride is usefulas a fertilizer.

In some embodiments, contacting 330 occurs after said extracting 320 asdepicted. In some embodiments, contacting 330 occurs after secondaryhydrolysis 240 (FIG. 26 a) conducted on sugar mixture 130 (131 a). Insome embodiments, contacting 330 occurs before chromatographicseparation 270 (FIG. 26 a). In some embodiments, contacting 330 is witha stream with acid concentration similar to that of secondary hydrolysis240. In some embodiments, contacting 330 lowers HCl concentration toless than 1, 0.9, 0.7, 0.5, 0.3 or 0.1% weight/weight or intermediate orlower concentrations of HCl on HCl/(HCl and water) basis. In someembodiments, the mixture after contacting 330 is concentrated prior tochromatographic separation (see 260 and 270 in FIG. 26 a). Optionally,the absence of acid at this stage contributes to a reduction inre-oligomerization and/or degradation of sugars to an insignificantlevel.

In some embodiments, the anion exchanger at contacting 330 is an aminecomprising at least 20 carbon atoms. In some embodiments, the amine is atertiaryamine, e.g. tri-octylamine, tri-caprylylamine, tri-decylamine ortri-laurylamine.

In some embodiments, method 300 includes decreasing an HCl concentrationin the super azeotropic HCl aqueous solution to prepare sugar mixture310 prior to extracting 320. In some embodiments, this decrease is arelative decrease of 2, 4, 6, 8, 10, 12, 14 or 16% weight/weight orintermediate or greater relative percentages. Optionally, evaporation at290 (FIG. 27 c) contributes to this reduction.

In some embodiments, method 300 includes increasing a sugarconcentration in sugar mixture 310 prior to extracting 320. In someembodiments, this increase is a relative increase of 2, 4, 6, 8, 10, 12,14 or 16% weight/weight or intermediate or greater relative percentages.Optionally, evaporation at 290 (FIG. 26 c) contributes to this increase.

Exemplary Product by Process

Some embodiments relate to a composition produced by a method 300. Insome embodiments, the composition includes at least 50% sugars by weighton an as is basis, at least 90% monomeric sugars relative to totalsugars and less than 0.3% HCl on as is basis. In some embodiments, therelative monomer concentration in the composition is 92, 94, 96, 97 or98% weight/weight or intermediate or greater percentages relative tototal sugars. In some embodiments, the composition includes at least 55,60, 65, 70 or 75% weight/weight total sugars by weight. In someembodiments, the composition includes less than 0.2, 0.1 or 0.05 HCl onas is basis.

Second Exemplary Method

FIG. 28 is a simplified flow diagram of a method of sugar refiningaccording to another exemplary embodiment of the invention depictedgenerally as 400. Method 400 includes feeding 410 a resin in achromatographic mode with an aqueous, low acid sugar mixture includingcellulosic monomeric and oligomeric sugars. In some embodiments, themethod includes incorporating sugars from secondary hydrolysis (e.g.,240 in FIG. 26 a) into the aqueous, low acid sugar mixture. The term“low acid” as used here and in the corresponding claims indicates lessthan 0.5, 0.4, 0.3, 0.2 or 0.1% weight/weight HCl on an as is basis. Insome embodiments, the sugar mixture is provided as an aqueous solution.Optionally, the mixture includes residual S1 solvent. Suitable resinsare described in “Exemplary Chromatography Resins” of this section.Optionally, a strong acid cation resin is employed.

In some embodiments, the sugar mixture includes at least 40%, 45%, 50%,51%, 52%, 53%, 54%, 55%, 56% or 58% weight/weight or intermediate orgreater concentrations of total sugars. Optionally, the sugar mixtureincludes 40 to 75% weight/weight total sugars by weight, in someembodiments about 45 to 60%, in some embodiments about 48 to 68%weight/weight.

Depicted exemplary method 400 includes feeding 420 the resin with anaqueous solution (optionally water) to produce an oligomer cut 422enriched in oligomeric sugars (compared to total sugars) relative to themixture fed at 410 and a monomer cut 424 enriched in monomeric sugars(relative to total sugars) relative to the mixture fed at 410. In someembodiments, monomer cut 424 is at least 80, 82, 84, 86, 88, 90, 92, 94,96 or 98% or intermediate or greater percentages monomeric sugars out oftotal sugars (by weight).

In some embodiments, the aqueous solution fed at 420 includes water froma previous evaporation step (e.g. 142 in FIG. 26 a). In someembodiments, the aqueous solution fed at 420 includes a stream ofhemicellulose sugars from a pressure wash as described in co-pendingapplication PCT/US2012/064541 (incorporated herein by reference for allpurposes).

Optionally, oligomer cut 422 includes at least 5, at least 10,optionally 20, optionally 30, optionally 40, optionally 50%weight/weight or intermediate or greater percentages of the total sugarsrecovered from the resin fed at 410.

In some embodiments, oligomer cut 422 is subject to adjustment. In someembodiments, adjustment includes hydrolyzing 430 oligomeric sugars inoligomer cut 422. Other adjustment strategies (not depicted) includeconcentration and/or water evaporation. In some embodiments, adjustmentincreases the ratio of monomers to oligomers. In some embodiments,hydrolyzing 430 is catalyzed by HCl at a concentration of not more than1.5%; 1.0%; 0.8, % 0.7%, 0.6%, or 0.5% weight/weight or intermediate orlower percentages on as is basis.

In those exemplary embodiments of the invention in which adjustmentinclude hydrolysis 430, a secondary hydrolysate 432 enriched withmonomeric sugars (relative to total sugars) is produced by hydrolysis ofat least a portion of the oligomeric sugars in oligomer cut 422 isproduced. Optionally, hydrolysis 430 is conducted together withhydrolysis 240 (FIG. 26 a) on a mixture of 131 a (FIG. 26 a) andoligomer cut 422. Optionally, oligomer cut 422 dilutes sugars in 131 aand this dilution improves hydrolysis kinetics.

In some embodiments, sugars from secondary hydrolysate 432 are used as aportion of the sugar mixture fed at 410 as indicated by the upwardarrow.

In some embodiments, hydrolyzing 430 is catalyzed by HCl at aconcentration of not more than 1.5%, 1.2%, 1%, 0.9%, 0.8%; 0.7%; 0.6% or0.5% weight/weight or intermediate or lower values on a weight basis. Insome embodiments, hydrolyzing 430 is catalyzed by HCl at a concentrationof 0.3 to 1.5%; 0.4 to 1.2% or 0.45 to 0.9% weight/weight. In someembodiments, hydrolyzing 430 is performed at a temperature between 60and 150° C.; between 70 and 140° C. or between 80 and 130° C.

In some embodiments, secondary hydrolysate 432 contains at least 70%; atleast 72%; 74%; 76%; 78%; 80%; 82%; 84%; 86%; 88% or 90% weight/weight;(or intermediate or greater percentages) monomeric sugars relative tothe total sugar content. In some embodiments, the total sugar content ofsecondary hydrolysate 432 is at least 86, 88, 90, 92, 94, 96, 98, 99 oreven 99.5% weight/weight or intermediate or greater percentages byweight of the sugar content of the mixture fed at 410.

In some embodiments, method 400 includes treating 409 the sugar mixtureincluding cellulosic monomeric and oligomeric sugars with an anionexchanger. According to these embodiments, the treated mixture from 409proceeds to 410 as depicted. In some embodiments, the anion exchangerincludes a weak base resin anion exchanger (WBA) and/or an anion anamine having at least 20 carbon atoms

Third Exemplary Method

FIG. 29 is a simplified flow diagram of a sugar refining methodaccording to another exemplary embodiment of the invention depictedgenerally as 500. Method 500 includes hydrolyzing 530 a mixture 510 ofoligomeric and monomeric sugars. Specifically, method 500 includesproviding 510 a mixture of oligomeric and monomeric sugars at a totalconcentration of at least 20, 22, 24, 26, 28, 30, 32, 34, 36 38 or 40%weight/weight or intermediate or greater percentages in an aqueoussolution of at least 1.5% HCl and/or less than 38% weight/weight HCl.

In some embodiments, the mixture provided at 510 has 20 to 38%, 22 to36%, 24 to 30% or 26 to 32% weight/weight HCl. In other exemplaryembodiments of the invention, the mixture provided at 510 has 1.7 to 6%,1.9 to 5.5%, 2.1 to 5%, 2.3 to 4.5% weight/weight HCl on as is basis. Insome embodiments, the mixture provided at 510 has 30% total sugarsand/or 27% HCl (e.g. if pre-evaporation 290 is present but extraction210 a is absent). In other exemplary embodiments of the invention, themixture provided at 510 has 25% total sugars and/or 33% HCl (e.g. ifpre-evaporation 290 and extraction 210 a are both absent). In someembodiments, the mixture provided at 510 includes at least 4% HCl; atleast 6% HCl or at least 8% HCl (by weight). In some embodiments, themixture provided at 510 includes less than 10% HCl; less than 8% HCl;less than 6% HCl or less than 4% HCl (by weight). In some embodiments,method 500 includes reducing 520 the sugar concentration in the mixturebelow 25%; below 22%; below 20%; below 18% or below 16% (by weight). Insome embodiments, the HCl concentration remains above 4, 6, 8 or 10after reducing 520.

Depicted exemplary method 500 includes hydrolyzing 530. Hydrolysis 530produces a secondary hydrolysate 532 enriched with monomeric sugars(relative to total sugars).

In some embodiments, method 500 includes contacting 540secondary-hydrolysate 532 with an anion exchanger. In some embodiments,contacting 540 facilitates separation 550 of sugars in hydrolysate 532from the catalyst of the reaction (e.g. HCl).

In some embodiments, separation 550 includes recovery of an aqueousde-acidified hydrolysate 552 from the HCl loaded anion exchanger 554. Insome embodiments, HCl 140 is washed from loaded anion exchanger 554 toregenerate the anion exchanger. In some embodiments, this regenerationis via washing with a base that forms a salt, so that 140 includes achloride salt and not HCl per se.

In some embodiments, the anion exchanger at 540 includes a weak baseresin anion exchanger (WBA) and/or an amine having at least 20 carbonatoms.

In some embodiments, hydrolysis 530 employs a mineral acid, such as HCl,as a catalyst. Optionally, enrichment results from hydrolysis of atleast a portion of the oligomeric sugars in the mixture. Optionally,hydrolysate 532 contains at least 72%, at least 78%, at least 82%, atleast 88%, at least 90% or at least 93% weight/weight monomeric sugarsor intermediate or higher percentages relative to the total amount ofsugars therein.

In some embodiments, HCl concentration in the mixture at 510 can be inthe range of 2 to 3%, e.g. 2.5 or 2.6% by weight. In some embodiments,hydrolysis 530 is catalyzed by 0.5; 0.6; 0.7; 0.8; 0.9; 1.0; 1.1; 1.2;1.3; 1.4 or 1.5% HCl, 0.3 to 1.5%; 0.4 to 1.2% or 0.45 to 0.9% by weighton as is basis. In some embodiments, hydrolyzing 530 is catalyzed by HClat a concentration of not more than 1.2%.

In some embodiments, the HCl percentage is reduced by diluting themixture prior to hydrolysis 530. In some embodiments, dilution is witholigomer cut 280 (see FIG. 26 a). In some embodiments, hydrolyzing 530is performed at a temperature in the range between 60° C. and 150° C.;70° C. and 140° C. or 80° C. and 130° C. Optionally, less than 1%non-hydrolytic degradation of sugars occurs during hydrolysis 530. Insome embodiments, the total sugar content of (secondary) hydrolysate 532is at least 90; 95; 97.5 or 99% (or intermediate or greater percentages)by weight of the sugar content of the mixture provided at 510. In someembodiments, hydrolysate 532 enriched with monomeric sugars contains atleast 70, at least 75, at least 80, at least 85 or at least 90% (orintermediate or greater percentages) by weight monomeric sugars out oftotal sugars.

In some embodiments, method 500 includes evaporating water 260 (see FIG.26 a) from hydrolysate 532. Optionally, at least part of thisevaporation occurs at a temperature of less than 70° C. or less 80° C.than Optionally, at least 63%, optionally at least 70% of the totalsugars are monomers after evaporation 260. In some embodiments, lessthan 10, 5, 2.5 or even less than 1% or intermediate or lowerpercentages of monomeric sugars in hydrolysate 532 oligomerize duringevaporation 260 (see FIG. 26 a).

In some embodiments, contacting 540 is prior to the evaporating (see 251and 260 in FIG. 26 a) and an aqueous, de-acidified hydrolysate 132 (FIG.26 a) is formed.

In some embodiments, method 500 includes removing 558 divalent cationsfrom aqueous, de-acidified hydrolysate 552 (optionally before theevaporation) with a cation exchanger. Optionally, removal 558 lowers thesugar concentration, since some water is added to wash sugars from thecation exchanger.

Depicted exemplary method 500 includes feeding 560 a resin in achromatographic mode (see 270 in FIG. 26 a) with hydrolysate 552(optionally after removal 558) and feeding 570 the resin with an aqueoussolution to produce an oligomer cut 572 enriched in oligomeric sugars(in proportion to total sugars) relative to hydrolysate 552 and amonomer cut 574 enriched in monomeric sugars (in proportion to totalsugars) relative to hydrolysate 552. Optionally, feeding 570 an aqueoussolution serves to release sugars from the resin. In some embodiments,the resin is an ion exchange resin.

Referring again to FIG. 26 a, feed 131 e to chromatographic separation270 is enriched in monomeric sugars relative to feed 131 a to secondaryhydrolysis 240, while monomer cut 230 from chromatographic treatment 270is enriched in monomeric sugars compared to feed stream 131 e.

Optionally, oligomer cut 572 is recycled (upwards arrow) so that themixture provided at 510 includes sugars from a previous oligomer cut572.

In some embodiments, method 500 includes separating 550 an HCl-loadedanion exchanger 554 from hydrolysate 532 to form aqueous, de-acidified(i.e. low acid) hydrolysate 552. Optionally, contacting 540 is prior toan evaporation procedure (see 260 in FIG. 26 a) and aqueous,de-acidified hydrolysate 552 is formed.

Fourth Exemplary Method

FIG. 32 is a simplified flow diagram of a method for increasing theratio of monomeric sugars to total sugars in an input sugar streamindicated generally as method 1000. In some embodiments, method 1000includes hydrolyzing 1010 oligomeric sugars in an input sugar stream1008 to produce an output stream 1012 including monomeric sugars. Insome embodiments, input stream 1008 is a mixture of monomeric andoligomeric sugars. In some embodiments, stream 1008 includes 30, 40, 50,60, 70 or 80% by weight oligomeric sugars (or intermediate or greaterpercentages) relative to total sugars. In some embodiments, stream 1008has a total sugar concentration of 20%, 25%, 30%, 35% or 40% orintermediate or greater concentrations. In some embodiments, stream 1008has an HCl/[HCl and water] concentration of 20%, 25%, 30% or 35% byweight or intermediate or greater concentrations.

In some embodiments, method 1000 includes chromatographically enriching1020 monomeric sugars from output stream 1012 to produce a monomer cut1030. In some embodiments, monomer cut 1030 includes 80%, 85%, 90%, 95%,97.5% or 99% by weight or more monomers as a percentage of total sugars.

In some embodiments, method 1000 includes at least two of the followingoptional actions:

(i) evaporating 1009 HCl (and/or water) 1007 from input sugar stream1008;(ii) contacting (1011 and/or 1014) input sugar stream 1008 and/or outputstream 1012 with an extractant (1013 and/or 1016) including an S1solvent; and(iii) contacting 1017 output stream 1012 with an anion exchanger 1019adapted to remove acid from the stream.

Some embodiments include only actions (i) and (ii). Other exemplaryembodiments of the invention include only actions (i) and (iii). Stillother exemplary embodiments of the invention include only actions (ii)and (iii). Still other exemplary embodiments of the invention includeall three of actions (i), (ii) and (iii). Among those embodiments of theinvention which include action (i), liquids 1007 optionally include HCland/or water. Optionally, evaporation 1009 serves to reduce HClconcentration and/or to increase total sugar concentration in stream1008. Among those embodiments which include action (ii), someembodiments include only contacting 1011 input sugar stream 1008 withextractant 1013 including an S1 solvent; other embodiments include onlycontacting 1014 output stream 1012 with extractant 1016 including an S1solvent; still other embodiments include both contacting 1011 inputsugar stream 1008 and contacting 1014 output stream 1012 with extractant1016 containing an S1 solvent. As depicted in FIG. 26 a, in someembodiments, extractant 1016 is re-used as extractant 1013 (See 210 aand 210 b of FIG. 26 a and accompanying explanation).

In some embodiments, method 1000 includes contacting 1011, extractant1013 and at least one of evaporation 1009 and contacting 1014 with anionexchanger 1019.

Fifth Exemplary Method

FIG. 33 is a simplified flow diagram of a sugar refining methodaccording to another exemplary embodiment of the invention depictedgenerally as 1100. Method 1100 includes de-acidifying 1109 a sugarmixture 1108 in a super azeotropic HCl aqueous solution. In someembodiments, the super azeotropic HCl aqueous solution is has an HClconcentration as described hereinabove. De-acidifying 1109 includesextracting 1110 with an extractant including an S1 solvent and thencontacting 1112 with an anion exchanger and chromatographicallyseparating 1120 an oligomer cut 1122 enriched in oligomeric sugarsrelative to sugar mixture 1108 and a monomer cut 1124 enriched inmonomeric sugars relative to sugar mixture 1108 on a weight basis. Insome embodiments, the anion exchanger at 1112 includes a weak base resin(WBA) and/or an amine comprising at least 20 carbon atoms.

In some embodiments, method 1100 includes hydrolyzing 1130 sugars fromoligomer cut 1122 to form monomeric sugars 1132.

Referring again to FIG. 26 a, method 1100 routes stream 131 a to anionexchanger 251 and routes stream 132 to chromatography component 270(optionally via cation exchanger 253 and/or evaporator 260 as depicted).

Exemplary Hybrid Method

Referring again to FIG. 26 a, in some embodiments a portion of stream131 a is routed to anion exchanger 251 without secondary hydrolysis at240 while a second portion of stream 131 a proceeds via secondaryhydrolysis 240 to anion exchanger 251. Both portions eventually reach achromatography component 270 (either the same one or different ones) andthe resultant oligomer cut(s) 280 is returned to secondary hydrolysis at240.

Exemplary Solvent Selection Considerations

In some embodiments, extraction 320 (FIG. 27) of the sugar mixture withthe S1 containing extractant results in a selective transfer orselective extraction of HCl from the sugar mixture to the extractant toform an S1/HCl-liquid phase (324) and an HCl-depleted sugar mixture(e.g. 131 a in FIG. 26 a).

The selectivity of extraction of HCl over water (S_(A/W)) can bedetermined by equilibrating hydrolysate with the extractant andanalyzing the concentrations of the acid and of the water in theequilibrated phases. In that case, the selectivity is:

S _(A/W)=(C _(A) /C _(W))org/(C _(A) /C _(W))aq

wherein (C_(A)/C_(W)) aq is the ratio between acid concentration andwater concentration in the aqueous phase and (C_(A)/C_(W)) org is theratio between acid concentration and water concentration in the organicphase.

S_(A/W) may depend on various parameters, such as temperature and thepresence of other solutes in the aqueous phase, e.g. carbohydrates.Selective extraction of acid over water means S_(A/W)>1.

In some embodiments, extraction 320 of HCl from sugar mixture 310provides, under at least some conditions, an S_(A/W) of at least about1.1, optionally at least about 1.3 and optionally at least about 1.5.

Similarly, selectivity to acid over a carbohydrate (S_(A/C)) can bedetermined by equilibrating the hydrolysate with said extractant andanalyzing the molar concentrations of the acid and the carbohydrate inthe equilibrated phases. In that case, the selectivity is:

S _(A/C)=(C _(A) /C _(C))org/(C _(A) /C _(C))aq.

wherein (C_(A)/C_(C)) aq is the ratio between acid concentration and theconcentration of the carbohydrate (or carbohydrates) in the aqueousphase and (C_(A)/C_(C)) org is the ratio of acid concentration and theconcentration of the carbohydrate (or carbohydrates) in the organicphase.

S_(A/C) may depend on various parameters, such as temperature and thepresence of other solutes in the aqueous phase, e.g. HCl. Selectiveextraction of acid over carbohydrate means S_(A/C)>1.

In some embodiments, extraction 320 of HCl from sugar mixture 310 by theextractant has, under at least some conditions, an S_(A/C) of at leastabout 2, optionally at least about 5 and optionally at least about 10.

N-hexanol has a relatively high SA/W and a relatively low SA/C.2-ethyl-1-hexanol has a relatively low SA/W and a relatively high SA/C.

These characteristics of the two hexanols caused previous efforts to usethem in the context of separating sugars from HCl to focus on combiningthe two of them, or using one of them in combination with acomplementary solvent (see for example U.S. Pat. No. 4,237,110 toForster et al.).

In some embodiments, n-hexanol or 2-ethyl-1-hexanol is employed as thesole S1 solvent in extraction 320.

Exemplary Primary Hydrolysis Efficiency

In some embodiments, at least 70% wt (optionally, more than 80, 90, 95%by weight) of polysaccharides in lignocellulosic substrate 112 hydrolyzeinto soluble carbohydrates in hydrolysis reactor 110. In someembodiments, the concentration of soluble carbohydrates in thehydrolysis medium increases with the progress of the hydrolysisreaction.

Exemplary Extractant Considerations

Optionally, the extractant includes a mixture of an alcohol and thecorresponding alkyl chloride. Optionally, the extractant includeshexanol and hexyl chloride. In some embodiments, the extractant includes2-ethyl-1-hexanol and 2-ethyl-1-hexyl chloride. Optionally, theextractant includes hexanol, 2-ethyl-1-hexanol, hexyl chloride and2-ethyl-1-hexyl chloride. Optionally, the alcohol/alkyl chloride w/wratio is greater than about 10 optionally greater than about 15,optionally greater than about 20, and optionally greater than about 30.In some embodiments, the extractant also includes water. In someembodiments, a non-carbohydrate impurity is selectively extracted intothe extractant, causing purification of the carbohydrate in extract 131a (FIG. 26 a). Optionally, the degree of selective extraction varies sothat 30%, optionally 40%, optionally 50%, optionally 60%, optionally70%; optionally 80%; optionally 90% or intermediate or greaterpercentages are achieved.

Exemplary Selective Transfer Parameters

Optionally, extraction 320 selectively transfers HCl from sugar mixture310 to the extractant to form extract 131 a and S1/HCl liquid phase 324.In some embodiments, at least 85% of the HCl from the sugar mixturetransfers to the extractant, at least 88%, at least 92% or at least 95%(by weight). In some embodiments, extract 131 a contains residual HCl.Optionally, the residual HCl is equivalent to about 0.1 to about 10% ofthe HCl in sugar mixture 310, optionally about 0.5 to about 8% andoptionally about 2 to about 7% by weight.

Exemplary Weight Ratios

In some embodiments, a total soluble carbohydrate concentration inoligomer cut 280 or 422 is in the range between 1% and 30%, optionallybetween 2% and 20% and optionally between 3% and 10% by weight. In someembodiments, HCl concentration in oligomer cut 422 is less than 0.2%,less than 0.1% or less than 0.05% by weight.

Exemplary Secondary Hydrolysis Conditions

In some embodiments, hydrolysis 430 (FIG. 28) and/or 340 (FIG. 27) ofoligomers in oligomer cut 422 (FIG. 28) is conducted at a temperaturegreater than 60° C., optionally between 70° C. and 130° C., optionallybetween 80° C. and 120° C. and optionally between 90° C. and 110° C. Insome embodiments, hydrolysis 430 and/or 340 proceeds at least 10minutes, optionally between 20 minutes and 6 hours, optionally between30 minutes and 4 hours and optionally between 45 minutes and 3 hours.

In some embodiments, secondary hydrolysis under these conditionsincreases the yield of monomeric sugars with little or no degradation ofsugars. In some embodiments, monomers as a fraction of total sugars isgreater than 70%, optionally greater than 80%, optionally greater than85% and optionally greater than 90% by weight after hydrolysis 340and/or 430. In some embodiments, degradation of monomeric sugars duringthe hydrolysis is less than 1%, optionally less than 0.2%, optionallyless than 0.1% and optionally less than 0.05% by weight.

Exemplary Chromatography Resins

Some embodiments employ an ion exchange (IE) resin (e.g. at 410 and/or270).

There are four main types of ion exchange resins differing in theirfunctional groups: strongly acidic (for example using sulfonic acidgroups such as sodium polystyrene sulfonate or polyAMPS), strongly basic(for example using quaternary amino groups, for example,trimethylammonium groups, e.g., polyAPTAC), weakly acidic (for exampleusing carboxylic acid groups) and weakly basic (for example usingprimary, secondary and/or ternary amino groups, such as polyethyleneamine).

Resins belonging to each of these four main types are commerciallyavailable. In some embodiments, resins of one or more of these fourtypes are employed.

In some embodiments, the resin employed at 410 (FIG. 28) and/or 270(FIG. 26 b) is a strong acid cation exchange resin in which sodium,potassium, or ammonium replace, at least partially hydrogen ions on theresin.

Strong acid cation resins include Purolite® resins such as PUROLITEResin PCR 642H+ and/or 642K (The Purolite Company, Bala Cynwood, Pa.,USA).

In some embodiments, purification media 274 (FIG. 26 b) includes aresin. Optionally, this resin is a mixed bed system using a combinationof strong cation resin and strong base anion resin. Mixed bed resinssuitable for use in this context are also available from The PuroliteCompany (Bala Cynwood, Pa., USA).

Exemplary Anion Exchangers

A wide variety of weak base resins (WBA) are commercially available.Many of these are suitable for use in the context of various embodimentsof the invention (e.g. at 251 in FIG. 26 a). Suitable resins includeDOWEX 66 (Dow Chemical Co.; USA) and A100 and/or A103S and/or A105and/or A109 and/or A111 and/or A120S and/or 1335 and/or A830 and/or A847(The Purolite Co.; USA).

In some embodiments, a wide variety of amine extractants with less than20 carbon atoms are available. Exemplary amine extractants suitable foruse in embodiments of the invention include tertiary amines, e.g.tri-octylamine, tri-caprylylamine, tri-decylamine or tri-laurylamine.

Exemplary IX

A wide variety of ion exchangers (IX) are commercially available. Manyof these are suitable for use in the context of various embodiments ofthe invention (e.g. at 253 in FIG. 26 a). Suitable resins include strongacid cation exchange resins such as DOWEX 88 (Dow Chemical Co.; USA) orC100 and/or C100E and/or C120E and/or C100X10 and/or SGC650 and/or C150and/or C160 (The Purolite Co.; USA).

Exemplary Equilibrium Considerations

HCl catalyzes both hydrolysis of oligomeric sugars and oligomerizationof monomeric sugars. Over a suitable period of time, an equilibriumwould be established. Reaction direction is influenced by sugarconcentration and ratio of monomers:oligomers. Reaction kinetics can beinfluenced by temperature and/or HCl concentration.

Referring again to FIG. 26 a and secondary hydrolysis unit 240: in someembodiments, the input sugar concentration has an excess of oligomersrelative to equilibrium conditions. Dilution with the oligomer cutreturning from chromatography unit 270 shifts the monomer:oligomerbalance even further away from equilibrium conditions. Under theseconditions, HCl drives the reaction in the direction of hydrolysis.

The sugar composition leaving hydrolysis unit 240 is much closer toequilibrium conditions, since oligomers have been hydrolyzed. However,evaporation 260 might shift the balance to monomeric excess. If thisoccurs, HCl would tend to catalyze re-oligomerization of monomers. Thechromatographic separation 270 is operated according to an embodiment ata sugars concentration significantly higher than that of secondaryhydrolysis 240. In order to avoid re-oligomerization during theconcentration of the sugars, acid 156 is removed by contacting with ananion exchanger 251 in some embodiments of the invention.

In equilibrium of the secondary hydrolysis reaction, the ratio betweenmonomeric sugars and oligomeric sugars is a function of the total sugarconcentration. The kinetics of the reaction is set by the temperatureand by the HCl concentration. The choice of temperature and HClconcentration is a matter of optimization, taking into account capitaland operating costs. In any case, equilibrium may be reached.Alternatively, the reaction may be stopped prior to reachingequilibrium. It is a matter of optimization of several factors such asdegradation of monomeric sugars and operational and capital costs. Insome embodiments, the secondary hydrolysis is stopped when it reaches atleast 70, 75, 80, 85, or 90% by weight of the equilibrium ratio orintermediate or greater percentages.

Exemplary Flow Control Considerations

In some embodiments, liquids with varying degrees of viscosity must betransported from one module or component to another. In someembodiments, sugar concentration and/or solvent concentration and/or HClconcentration contribute to the viscosity of a solution. In someembodiments, this transport relies, at least partially, upon gravity. Insome embodiments, pumps may be employed to transport liquids. In someembodiments, liquids move in different directions and/or at differentrates. Optionally, some liquids are held in reservoirs for later use. Insome embodiments, a controller serves to regulate one or more liquidflows.

FIG. 30 is a schematic representation indicating flow control componentsof a sugar refining module similar to that of FIG. 26 a indicatedgenerally as 800. In the context of system 100, module 800 is analogousto module 200. Numbers beginning with the numeral “1” refer to solutionsor streams described hereinabove. Many of the numbers beginning with thenumeral “8” refer to similar numbers beginning with the numeral “2” inFIG. 26 a and are described only in terms of their relation to flowcontrol components here.

In some embodiments, pump 811 a provides a flow of S1 based extractant155 through acid extractors 810 a and 810 b. The flow carries HCl 140along with it. The extractors are arranged in series and the flow ispumped through 810 b to 810 a. In some embodiments, a single extractor810 is used.

Pump 812 a provides a flow of sugar mixture 130 to acid extractor(s) 810a. In some embodiments, controller 890 regulates flow rates of pumps 812a and 811 a to insure efficient extraction of acid by the extractant.Optionally, a correct relative flow rate contributes to this efficiency.In some embodiments, pumps 812 a and 811 a are provided as part of aBateman pulsed column as described hereinabove. In some embodiments,flow rates in pumps 812 a and/or 811 a are varied to adapt acidextractor 810 a to provide a desired degree of extraction efficiency.

In some embodiments, acid-reduced stream 131 a emerges from extractor810 a and is drawn through secondary hydrolysis module 840 by pump 842.Again, controller 890 regulates a flow rate through module 840 to insurethat a desired degree of hydrolysis is achieved. Optionally, anadditional pump 832 moves stream 131 a to secondary hydrolysis module840 as depicted. The resultant secondary hydrolysate 131 b is pumped tofiltration unit 850. Optionally, filtration pump 852 draws hydrolysate131 b through filters in the unit and/or pumps filtered secondaryhydrolysate 131 c to anion exchanger 851. In some embodiments, aseparate pump 848 periodically provides a rinse flow (rightward pointingarrow) to filtration unit 850 to wash accumulated debris from thefilters. In some embodiments, controller 890 coordinates operation ofpumps 848 with 842 and/or 852 to assure proper operation of filter unit850.

In some embodiments, filtered stream 131 c is pumped through anionexchanger 851 by pump 854 to produce a de-acidified hydrolysate 132. Insome embodiments, a separate pump 849 delivers a wash stream to anionexchanger 851 to produce a dilute stream of HCl 156. In someembodiments, controller 890 coordinates operation of pumps 854 with 849and/or 856 to assure proper operation of anion exchanger 851.

In some embodiments, pump 856 draws de-acidified hydrolysate 132 throughcation exchanger module 853. Output stream 131 d is reduced in cationcontent. In some embodiments, a separate pump 852 delivers a wash streamto module 853 to produce a stream of eluted cations 157. In someembodiments, controller 890 coordinates operation of pumps 852 with 856and/or 862 to assure proper operation of module 853.

In some embodiments, exit stream 131 d is drawn into evaporation unit860 by pump 862 which increases the sugar concentration by evaporatingwater. The resultant concentrated filtered secondary hydrolysate 131 eis pumped to chromatography component 870 by pump 872.

In some embodiments, water 142 produced by evaporator 860 is pumped bycollection mechanism 864 to chromatography unit 870 for use as anelution fluid. Since chromatography unit 870 cyclically alternatesbetween sample feeding and elution in some embodiments, collectionmechanism 864 optionally includes a water reservoir as well as a pump.

In some embodiments, controller 890 coordinates action of collectionmechanism 864 and pump 872 to cyclically feed the resin inchromatography unit 870 with a sample stream and an elution stream. Thiscyclic feeding and elution produces an oligomer cut 280 which isrecycled to hydrolysis unit 840 by pump 872 and a monomer cut 230 whichis optionally pumped by pump 872 to module 204 (FIG. 26 b).

Optionally, controller 890 responds to feedback from sensors (notdepicted) positioned at entrances and/or exits of various modules and/orunits. In some embodiments, these sensors include flow sensors andcontroller 890 regulates relative flow rates. In some embodiments, adivision between the oligomer cut and the monomer cut is made based uponhistorical performance data of the resin in chromatography unit 870 interms of bed volumes of effluent after sample feeding.

In some embodiments, the sensors include parametric detectors.Optionally, the parametric detectors monitor sugar concentration and/oracid concentration. In some embodiments, sugar concentration is measuredby assaying refractive index and/or viscosity. Optionally, acidconcentration is monitored by pH measurement. In some embodiments, adivision between the oligomer cut and the monomer cut is made based uponactual performance data of the resin in chromatography unit 870 in termsof concentration of specific sugars as assayed by refractive indexand/or acid concentration as estimated from pH.

Exemplary Monomer Concentrations

Referring again to FIG. 26 a, in various exemplary embodiments of theinvention, monomeric sugar enriched mixture 131 b produced by secondaryhydrolysis 240 includes 72, 74, 76, 78, 80, 82, 84, 86, 88 or 90% byweight by weight or intermediate or greater percentages of monomericsugars by weight relative to total sugars. In some embodiments, invarious exemplary embodiments of the invention, monomer cut 230 fromchromatography 270 includes 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 99or 99.5% by weight or intermediate or greater percentages of monomericsugars by weight relative to total sugars.

Exemplary Orders of Operations

Referring again to FIG. 26 a, many exemplary embodiments of theinvention include secondary hydrolysis unit 240 and chromatographycomponent 270 and various combinations of other components and/or units.

In some embodiments, sugars from stream 130 proceed directly tosecondary hydrolysis unit 240 and secondary hydrolysate 131 b proceeds(optionally via filtration unit 250) to acid extractor 210 b, to anionexchanger 251 and then (optionally via cation exchanger module 253) andthen to evaporation unit 260 and then to chromatography unit 270.

In some embodiments, sugars from stream 130 proceed directly tosecondary hydrolysis unit 240 and secondary hydrolysate 131 b proceeds(optionally via filtration unit 250) to acid extractor 210 b and then toevaporation unit 260 and then to chromatography unit 270.

In some embodiments, stream 130 is pre-evaporated at 290 (FIG. 26 c) andthen sugars from stream 130 proceed to secondary hydrolysis unit 240 andsecondary hydrolysate 131 b proceeds (optionally via filtration unit250) to acid extractor 210 b, to anion exchanger 251 and then(optionally via cation exchanger module 253) and then to evaporationunit 260 and then to chromatography unit 270.

In some embodiments, stream 130 is pre-evaporated at 290 (FIG. 26 c) andthen sugars from stream 130 proceed to secondary hydrolysis unit 240 andsecondary hydrolysate 131 b proceeds (optionally via filtration unit250) to acid extractor 210 b and then to evaporation unit 260 and thento chromatography unit 270.

In some embodiments, stream 130 is extracted at acid extractor 210 a andthen sugars from stream 130 proceed to secondary hydrolysis unit 240 andsecondary hydrolysate 131 b proceeds (optionally via filtration unit250) to acid extractor 210 b, to anion exchanger 251 and then(optionally via cation exchanger module 253) and then to evaporationunit 260 and then to chromatography unit 270.

In some embodiments, stream 130 is pre-evaporated at 290 (FIG. 26 c),extracted at acid extractor 210 a and then sugars from stream 130proceed to secondary hydrolysis unit 240 and secondary hydrolysate 131 bproceeds (optionally via filtration unit 250) to acid extractor 210 b,to anion exchanger 251 and then (optionally via cation exchanger module253) and then to evaporation unit 260 and then to chromatography unit270.

In some embodiments, stream 130 is pre-evaporated at 290 (FIG. 26 c),extracted at acid extractor 210 a and then sugars from stream 130proceed to secondary hydrolysis unit 240 and secondary hydrolysate 131 bproceeds (optionally via filtration unit 250) to acid extractor 210 b,to evaporation unit 260 and then to chromatography unit 270.

In some embodiments, stream 130 is pre-evaporated at 290 (FIG. 26 c),extracted at acid extractor 210 a and then sugars from stream 130proceed to secondary hydrolysis unit 240 and secondary hydrolysate 131 bproceeds (optionally via filtration unit 250) to evaporation unit 260and then to chromatography unit 270.

In some embodiments, stream 130 is extracted at acid extractor 210 a andthen sugars from stream 130 proceed to secondary hydrolysis unit 240 andsecondary hydrolysate 131 b proceeds (optionally via filtration unit250) to evaporation unit 260 and then to chromatography unit 270.

Additional Exemplary Methods and Related Products

FIG. 31 a is a simplified flow diagram of a method according to anotherexemplary embodiment of the invention depicted generally as 900. Method900 includes providing 910 a fermentor and fermenting 920 a mediumincluding monomeric sugars to produce a conversion product 930. In someinstances processes depicted in FIGS. 25 and 26 a and/or 26 b and/or 26c are conducted in a single plant or system together with fermenting920.

FIG. 31 b is a simplified flow diagram of a method according to anotherexemplary embodiment of the invention depicted generally as 901. Method901 includes providing 911 a monomeric sugar containing solution andconverting sugars in the solution to a conversion product 931 using achemical process 921.

In some embodiments, the monomeric sugars, or monomeric sugar containingsolution, may be provided as monomeric sugar enriched mixture (e.g. 342or 1032) and/or as a monomer cut (e.g. 230 or 574) and/or as ahydrolysate containing monomeric sugars (e.g. 510, 532 or 552).

In some embodiments, fermentation 920 and/or chemical process 921 are asdescribed in U.S. Pat. No. 7,629,010; U.S. Pat. No. 6,833,149; U.S. Pat.No. 6,610,867; U.S. Pat. No. 6,452,051; U.S. Pat. No. 6,229,046; U.S.Pat. No. 6,207,209; U.S. Pat. No. 5,959,128; U.S. Pat. No. 5,859,270;U.S. Pat. No. 5,847,238; U.S. Pat. No. 5,602,286; and U.S. Pat. No.5,357,035, the contents of which are incorporated by reference. Invarious embodiments, the processes described in the above US patents arecombined with one or more methods as described herein, for example, withsecondary hydrolysis and/or chromatography as described herein.

In some embodiments, fermentation 920 may employ a genetically modifiedorganism (GMO). A wide range of GMOs are potentially compatible withsugars produced by the methods described herein. GMOs may includemembers of the genera Clostridium, Escherichia, Salmonella, Zymomonas,Rhodococcus, Pseudomonas, Bacillus, Enterococcus, Alcaligenes,Lactobacillus, Klebsiella, Paenibacillus, Corynebacterium,Brevibacterium, Pichia, Candida, Hansenula and Saccharomyces. Hosts thatmay be particularly of interest include Oligotropha carboxidovorans,Escherichia coli, Bacillus licheniformis, Paenibacillus macerans,Rhodococcus erythropolis, Pseudomonas putida, Lactobacillus plantarum,Enterococcus faecium, Enterococcus gallinarium, Enterococcus faecalis,Bacillus subtilis and Saccharomyces cerevisiae. Also, any of the knownstrains of these species may be utilized as a starting microorganism. Invarious exemplary embodiments, the microorganism is an actinomyceteselected from Streptomyces coelicolor, Streptomyces lividans,Streptomyces hygroscopicus, or Saccharopolyspora erytraea. In variousexemplary embodiments, the microorganism is a eubacterium selected fromEscherichia coli, Pseudomonas fluorescens, Pseudomonas putida,Pseudomonas aeruginosa, Bacillus subtilis or Bacillus cereus.

In some exemplary embodiments, the GMO is a gram-negative bacterium. Insome exemplary embodiments, the recombinant microorganism is selectedfrom the genera Zymomonas, Escherichia, Alcaligenes and Klebsiella. Insome exemplary embodiments, the recombinant microorganism is selectedfrom the species Escherichia coli, Cupriavidus necator and Oligotrophacarboxidovorans. In some exemplary embodiments, the recombinantmicroorganism is an E. coli strain.

In some embodiments, fermentation 920 produces lactic acid as conversionproduct 930. The potential of lactic acid as a commodity chemical, forexample for use in the production of various industrial polymers, isknown. This has been described, for example, in U.S. Pat. Nos.5,142,023; 5,247,058; 5,258,488; 5,357,035; 5,338,822; 5,446,123;5,539,081; 5,525,706; 5,475,080; 5,359,026; 5,484,881; 5,585,191;5,536,807; 5,247,059; 5,274,073; 5,510,526; and 5,594,095. (The completedisclosures of these seventeen patents, which are owned by Cargill, Inc.of Minneapolis, Minn., are incorporated herein by reference.) There hasbeen general interest in developing improved techniques for generationand isolation of lactic acid. Also, because of their potentialcommercial value, there is great interest in isolation of the othervaluable related lactate products such as lactide, lactate esters andamides, and oligomers; see e.g. the same 17 patents.

In general, large amounts of lactic acid can be readily generated by theconduct of large-scale, industrial, microbial fermentation processes,particularly using sugars produced by exemplary methods as describedherein, such as dextrose, in the media, along with suitable mineral andamino acid based nutrients. Typically, such productions occur at brothtemperatures of at least 45° C., usually around 48° C.

Issues of concern with respect to lactic acid generation include, interalia, appropriate control of pH within the fermentation system to ensureproper environment for microbial action, separation and isolation ofeither or both of lactic acid and lactate salts from the fermentationprocess and downstream isolation and production involving the isolatedlactic acid or lactic acid derived product.

In some embodiments, the sugars produced by the exemplary methodsdescribed herein are incorporated into a fermentation product asdescribed in the following US patents, the contents of each of which arehereby incorporated by reference: U.S. Pat. No. 7,678,768; U.S. Pat. No.7,534,597; U.S. Pat. No. 7,186,856; U.S. Pat. No. 7,144,977; U.S. Pat.No. 7,019,170; U.S. Pat. No. 6,693,188; U.S. Pat. No. 6,534,679; U.S.Pat. No. 6,452,051; U.S. Pat. No. 6,361,990; U.S. Pat. No. 6,320,077;U.S. Pat. No. 6,229,046; U.S. Pat. No. 6,187,951; U.S. Pat. No.6,160,173; U.S. Pat. No. 6,087,532; U.S. Pat. No. 5,892,109; U.S. Pat.No. 5,780,678; and U.S. Pat. No. 5,510,526.

In some embodiments, the conversion product (930 or 931) can be, forexample, an alcohol, carboxylic acid, amino acid, monomer for thepolymer industry or protein. In some embodiments, the conversion product(930 or 931) is processed to produce a consumer product selected fromthe group consisting of a detergent, a polyethylene-based product, apolypropylene-based product, a polyolefin-based product, a polylacticacid (polylactide)-based product, a polyhydroxyalkanoate-based productand a polyacrylic-based product. Optionally, the detergent includes asugar-based surfactant, a fatty acid-based surfactant, a fattyalcohol-based surfactant or a cell-culture derived enzyme. Optionally,the polyacrylic-based product is a plastic, a floor polish, a carpet, apaint, a coating, an adhesive, a dispersion, a flocculant, an elastomer,an acrylic glass, an absorbent article, an incontinence pad, a sanitarynapkin, a feminine hygiene product and a diaper. Optionally, thepolyolefin-based products is a milk jug, a detergent bottle, a margarinetub, a garbage container, a plumbing pipe, an absorbent article, adiaper, a non-woven, an HDPE toy or an HDPE detergent packaging.Optionally, the polypropylene based product is an absorbent article, adiaper or a non-woven. Optionally, the polylactic acid based product isa packaging of an agriculture product or of a dairy product, a plasticbottle, a biodegradable product or a disposable. Optionally, thepolyhydroxyalkanoate based products is packaging of an agricultureproduct, a plastic bottle, a coated paper, a molded or extruded article,a feminine hygiene product, a tampon applicator, an absorbent article, adisposable non-woven or wipe, a medical surgical garment, an adhesive,an elastomer, a film, a coating, an aqueous dispersant, a fiber, anintermediate of a pharmaceutical or a binder. Optionally, conversionproduct 930 or 931 is ethanol, butanol, isobutanol, a fatty acid, afatty acid ester, a fatty alcohol or biodiesel.

In some embodiments, method 900 or 901 includes processing of conversionproduct 930 or 931 to produce at least one product such as, for example,an isobutene condensation product, jet fuel, gasoline, gasohol, dieselfuel, drop-in fuel, diesel fuel additive or a precursor thereof.

Optionally, the gasohol is ethanol-enriched gasoline and/orbutanol-enriched gasoline.

In some embodiments, the product produced from conversion product 930 or931 is diesel fuel, gasoline, jet fuel or a drop-in fuel.

Various exemplary embodiments of the invention include consumerproducts, precursors of consumer product, and ingredients of consumerproducts produced from conversion product 930 or 931.

Optionally, the consumer product, precursor of a consumer product, oringredient of a consumer product includes at least one conversionproduct 930 or 931 such as, for example, a carboxylic or fatty acid, adicarboxylic acid, a hydroxylcarboxylic acid, a hydroxyldicarboxylicacid, a hydroxyl-fatty acid, methylglyoxal, mono-, di-, or poly-alcohol,an alkane, an alkene, an aromatic, an aldehyde, a ketone, an ester, abiopolymer, a protein, a peptide, an amino acid, a vitamin, anantibiotics and a pharmaceutical.

For example, the product may be ethanol-enriched gasoline, jet fuel, orbiodiesel.

Optionally, the consumer product has a ratio of carbon-14 to carbon-12of about 2.0×10⁻¹³ or greater. Optionally, the consumer product includesan ingredient of a consumer product as described above and an additionalingredient produced from a raw material other than lignocellulosicmaterial. In some embodiments, ingredient and the additional ingredientproduced from a raw material other than lignocellulosic material areessentially of the same chemical composition. Optionally, the consumerproduct includes a marker molecule at a concentration of at least 100ppb.

In some embodiments, the marker molecule can be, for example, furfural,hydroxymethylfurfural, products of furfural or hydroxymethylfurfuralcondensation, color compounds derived from sugar caramelization,levulinic acid, acetic acid, methanol, galacturonic acid or glycerol.

XIII. Alternative Lignin Processing Embodiments

FIG. 25 is a schematic representation of an exemplary hydrolysis systemwhich produces a lignin stream that serves as an input stream indicatedgenerally as 100. System 100 includes a hydrolysis vessel 110 whichtakes in lignocellulosic substrate 112 and produces two exit streams.The first exit stream is an acidic hydrolysate 130 containing an aqueoussolution of HCl with dissolved sugars. The second exit stream 120 is alignin stream. Processing of lignin stream 120 to remove HCl and wateris one focus of this application. Recycling of the removed HCl is anadditional focus of this application. Ways to accomplish this recyclingwithout diluting the HCl are an important feature of some exemplaryembodiments described herein. In some embodiments, lignin stream 120contains less than 5%, less than 3.5%, less than 2% or less than 1%weight/weight cellulose relative to lignin on a dry matter basis.

In some embodiments, hydrolysis vessel 110 is of the type described inco-pending international application PCT/US2011/057552 (incorporatedherein by reference for all purposes). In some embodiments, thehydrolysis vessel may include hydrolysis reactors of one or more othertypes. In some embodiments, substrate 112 contains pine wood. Processingof hydrolysate stream 130 occurs in sugar refining module 201 andproduces refined sugars 230 which are substantially free of residualHCl. For purposes of the overview of system 100, it is sufficient tonote that module 201 produces a re-cycled stream 140 of concentrated HClwhich is routed to hydrolysis vessel 110. In some embodiments, HCl 140is recovered from hydrolysate 130 by extracting with a solvent basedextractant 155. Optionally, this extraction occurs in refining module201. In some embodiments, extractant 155 is separated from HCl 140 insolvent recovery module 150. In some embodiments, lignin stream 120includes significant amounts of HCl and dissolved sugars.

Exemplary Method

FIG. 34 is a simplified flow diagram of a method for processing a ligninstream indicated generally as 200. Feed stream 208 corresponds to ligninstream 120 of FIG. 25.

Method 200 includes washing (210 a and/or 210 b) a feed stream 208. Feedstream 208 includes one or more sugars dissolved in an aqueoussuper-azeotropic HCl solution and solid lignin. In many cases the solidlignin in stream 208 is wetted by, or impregnated with, the solution. Insome embodiments, washing (210 a and/or 210 b) serves to remove sugarsfrom the lignin. In some embodiments, washing (210 a and/or 210 b) areperformed with a washing-HCl solution (207 a and/or 207 b) including atleast 5% wt HCl to form a washed sugars solution (212 a and/or 212 b)and a washed lignin stream 214. In some embodiments, washed ligninstream 214 includes solid lignin, water and HCl.

Method 200 also includes contacting 220 washed lignin stream 214 withrecycled hydrocarbon 218 to form a de-acidified lignin 222 stream and avapor phase 224 containing HCl and water. In some embodiments,contacting 220 of recycled hydrocarbon 218 with washed lignin stream 222occurs at 65, 70, 75, 80, 85 or 90° C. or intermediate or highertemperatures. Optionally, contacting 220 is conducted at a temperatureat which hydrocarbon 218 boils. In some embodiments, vapor phase 224also contains hydrocarbon 218 (not depicted). In some embodiments,de-acidified lignin stream 222 includes solid lignin and less than 2%HCl by weight.

In some embodiments, method 200 includes condensing 230 vapor phase 224to form a condensed aqueous HCl solution 232. In some embodiments,method 200 includes using 234 condensed aqueous HCl solution 232 inwashing 210 a and/or 210 b. In some embodiments, method 200 includeusing 236 condensed aqueous HCl solution 232 in hydrolysis 110 of alignocellulosic material 112 (see FIG. 25). In some embodiments,condensing 230 produces additional recovered hydrocarbon 231 (notdepicted). In some embodiments, recovered hydrocarbon 231 is recycled233 from de-acidified lignin 222 to 218. In some embodiments, recycling233 includes one or more of centrifugation, vapor condensation,evaporation and distillation.

Exemplary Washing Considerations

In some embodiments, a concentration of lignin in feed stream at 208 isbetween 5% and 50%, 15% and 45%, 20% and 40% or 25% and 35%weight/weight on as is basis. In some embodiments, in some embodiments aconcentration of HCl in feed stream is between 35 and 45%, 37% and 44%,38% and 43% or 39% and 42.5% weight/weight HCl/[HCl and water]. In someembodiments, a concentration of sugar in stream 208 is between 5% and35%, 10% and 30%, 12% and 27%, 15% and 25% weight/weight on as is basis.

In some embodiments, glucose contains at least 50%, at least 60%, atleast 70%, at least 80% or at least 90% weight/weight of the totalsugars in feed stream 208. In some embodiments, glucose contains 50% to80%, 50% to 85%, 50% to 90%, 50% to 95%, 50% to 99%, 60% to 80%, 60% to85%, 60% to 90%, 60% to 95% or 60% to 99% weight/weight of the totalsugar in feed stream 208. In some embodiments, stream 208 contains oneor more C5 sugars and the C5 sugars are less than 50, less than 40, lessthan 30, less than 20, less than 10 or less than 5% of the total sugarsin stream 208.

In some embodiments, washing 210 a and/or 210 b of feed stream 208includes at least one counter current contacting. In some embodiments,an HCl concentration in solution 207 a and/or 207 b is at least 20, atleast 25, at least 30, at least 35 or at least 40 wt %.

In some embodiments, washing feed stream 208 includes a first countercurrent contacting 210 a with a first solution 207 a containing at least5% wt HCl to form a first washed sugars solution 212 a and a secondcounter current contacting 210 b with a second solution 207 b containingat least 5% wt HCl to form a second washed sugars solution 212 b. Insome embodiments, an HCl concentration in first solution 207 a is atleast 35, at least 37, at least 39, at least 41 or at least 42% wt. Insome embodiments, an HCl concentration in second solution 207 b is atleast 20, at least 25, at least 28, at least 30 or at least 32% wt. Insome embodiments, a sugar concentration in washed lignin stream 214 isless than 5%, 4%, 3%, 2% or 1% on as is basis.

In some embodiments, the number of wash stages varies. In FIG. 34 twowash stages are depicted (210 a and 210 b). In other exemplaryembodiments of the invention, a larger number of wash stages isimplemented. For example, three to ten wash stages are implemented insome embodiments of the invention. In some embodiments, a temperature ofthe wash changes between stages. For example, in some embodiments thelast stage or stages are conducted at a slightly elevated temperaturecompared with early stages, e.g. 25° C. to 40° C., compared with 10° C.to 20° C. In some embodiments, each wash stage is carried out in ahydro-cyclone. Optionally, pressure in the hydro-cyclones is 40 to 90psig. In some embodiments, two wash streams (207 a and 207 b) serve morethan two hydro-cyclones. In some embodiments, wash stream 207 a has anHCl concentration of 40 to 43% and wash stream 207 b has an HClconcentration of 32 to 36%. In some embodiments, stream 207 a enters thefirst hydro-cyclone (from the standpoint of feed stream 208) and stream207 b enters the last hydro-cyclone (from the standpoint of feed stream208). Optionally, washing temperature increases as HCl concentrationdecreases in the wash.

Exemplary Optional Grinding

In some embodiments, wet grinding of feed stream 208 prior to washing210 (210 a and/or 210 b) is conducted. Optionally, the wet grindingcontributes to an increase in efficiency of washing. In someembodiments, wet grinding of stream 214 prior to contacting 220 isconducted. Optionally, the wet grinding contributes to an increase inefficiency of de-acidification. This increased efficiency is in terms ofa reduced time for contacting 220 and/or a reduction in the ratio ofwash stream 210 a and/or 210 b to feed stream 208.

Exemplary Contacting Considerations

In some embodiments, the hydrocarbon employed at contacting 220 has aboiling point at atmospheric pressure between 100° C. and 250° C., 120°C. and 230° C. or 140° C. and 210° C. Suitable hydrocarbons includeisoparaffinic fluids (e.g. ISOPAR G, H, J, K, L or M from ExxonMobilChemical, USA). In some embodiments, the selected isoparaffinic fluid issubstantially insoluble in water. In some embodiments, dodecane isemployed as a hydrocarbon 218 at contacting 220.

In some embodiments, 9 parts of Isopar K as hydrocarbon 218 arecontacted 220 with 1 part of washed lignin stream 214 (e.g. about 20%solid lignin on as is basis). According to these embodiments, a ratio ofIsopar K to dry lignin is about 7/1; 9/1; 11/1; 15/1; 30/1; 40/1 or 45/1w/w (or intermediate or greater ratios) is contacted in 220.

In some embodiments, washing 210 a and/or 210 b is at a pressure between40 and 90 psig. In some embodiments, contacting 220 is conducted atatmospheric pressure. In some embodiments, de-acidified lignin stream222 includes less than 2%, less than 1.5%, less than 1.0%, less than0.5%, less than 0.3%, less than, 0.2% or less than 0.1% HClweight/weight on as is basis. In some embodiments, de-acidified ligninstream 222 contains at least at least 60%, at least 70%, at least 80%,at least 90%, at least 95%, at least 96%, at least 97%, at least 98% orat least 99% weight/weight solid lignin on as is basis.

Exemplary Condensing Considerations

In some embodiments, an HCl concentration in condensed aqueous HClsolution 232 is greater than 20%, greater than 22%, greater than 24%,greater than 26% or greater than 28% weight/weight as HCl/(HCl andwater).

Additional Exemplary Recycling Loops

In some embodiments, method 200 includes using washed sugars solution212 a or 212 b in hydrolyzing a lignocellulosic material (e.g. at 110 inFIG. 25). In some embodiments, method 200 includes using first washedsugars solution 212 a in hydrolysis of a lignocellulosic material. Insome embodiments, method 200 includes using second washed sugarssolution 212 b in hydrolysis of a lignocellulosic material.

Exemplary Hydrolysis Considerations

In some embodiments, lignocellulosic material 112 (FIG. 25) includessoftwood (e.g. pine). In some embodiments, lignocellulosic material 112includes hardwood (e.g. eucalyptus or oak). In some embodiments, atemperature of hydrolyzing at 110 (FIG. 25) is less than 25, less than23, less than 21, less than 19, less than 17 or, less than 15° C.

Second Exemplary Method

FIG. 35 is a simplified flow diagram of a method for processing a ligninstream indicated generally as 300 according to some embodiments. In someembodiments, feed stream 308 corresponds to lignin stream 120 of FIG.25.

Method 300 includes de-acidifying 310 a feed stream 308 containing solidlignin, an aqueous super-azeotropic HCl solution and at least one sugarto form a de-acidified lignin stream 312. In some embodiments, stream312 includes solid lignin and less than 2%, less than 1.5%, less than1.0%, less than 0.5%, less than 0.3%, less than 0.2 or less than 0.1%HCl weight/weight on as is basis. In some embodiments, stream 312includes lignin which is at least 70%, at least 75%, least 80%, at least85%, least 90% or at least 95% weight/weight solid (or intermediate orgreater percentages).

The depicted method also includes cooking 320 the solid lignin of 312 inan alkali solution 318 to form an alkaline solution 322 includingdissolved lignin. In some embodiments, the yield of lignin dissolved inalkaline solution 322 is at least 85%, 90%, 92.5%, 95%, 97.5%, 99%,99.5% or substantially 100% weight/weight of the amount of lignin instream 312. In some embodiments, the concentration of dissolved ligninat 322 is at least 5%, 7%, 8%, 10%, 15%, 20% or 25% weight/weight orintermediate or greater percentages (expressed as dissolved solids). Insome embodiments, cooking 320 is conducted at a temperature greater than100° C., greater than 110° C., greater than 120° C. or greater than 130°C. In some embodiments, cooking 320 is conducted at a temperature lowerthan 200° C., lower than 190° C., lower than 180° C., lower than 170°C., lower than 160° C. or lower than 150° C. In some embodiments,cooking 320 is conducted at a temperature between 160° C. and 220° C.,170° C. and 210° C., 180° C. and 200° C., or 182° C. and 190° C. In someembodiments, cooking 320 has a duration of at least 10, at least 20, atleast 30, at least 40, at least 50, at least 60, at least 70, at least80, at least 90 or at least 120 minutes. In some embodiments, cooking320 has a duration of less than 10, less than 9, less than 8, less than7, less than 6, less than 5.5, less than 5, less than 4.5, less than 4or less than 3.5 hours. In some embodiments, the cooking time is about 6hours (e.g. at 182° C.). In some embodiments, an increase in cookingtime and/or in cooking temperature contributes to an increase in ligninfragmentation and/or degradation. In some embodiments, cooking 320 iscooking in an alkali solution containing less than 20%, less than 15%,less than 10%, less than 5% or less than 2% solvent. Optionally, cooking320 is cooking in an alkali solution that is substantially free ofsolvent. Cooking 320 is conducted on a composition that is practicallyfree of cellulose so that it is very different from wood pulping.

In some embodiments, an alkaline concentration of alkaline solution 318is adjusted so that the alkaline concentration at 320 is at least 5%,6%; 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15% weight/weight orintermediate or greater percentages when expressed as 100× base/(baseand water) on a weight basis. The table below illustrates exemplaryamounts and relationships of components at cooking 320 from laboratoryscale experiments.

Exemplary conditions from laboratory scale experiments NaOH/(NaOH +Lignin/ water) × Line Lignin (g) NaOH (g) NaOH Water (g) 100 1 50 20 2.5200 9% 2 60 20 3.0 200 9% 3 20 14 1.4 200 6.5%   4 75 30 2.5 200 13% 

The lab scale conditions from line 3 of Table 1 were scaled up to asemi-industrial procedure as follows:

30 lbs Lignin at 50% moisture/volatiles (15 lbs dry Lignin solids)10.5 lbs NaOH dry solids provided as 50% caustic solution150 lbs water (includes 10.5 lbs water in the 50% caustic solution)15 lbs IsoPar K (in the wet lignin; residual solvent at 222 in FIG. 34)

In the scaled semi-industrial procedure the ratio of lignin/NaOH was1.42 and the alkaline concentration was 6.5% (compare to line 3 in thetable above).

In some embodiments, lignin stream 312 contains residual hydrocarbon(e.g. dodecane) from de-acidification 310. Upon cooking 320, the ligninin stream 312 dissolves into the alkaline aqueous phase, so that theresidual hydrocarbon separates easily into a separate organic phasewhich is decanted and recycled. In some embodiments, alkali solution 318includes ammonia and/or sodium hydroxide and/or sodium carbonate.

Method 300 includes purifying 330 the dissolved lignin to form purifiedlignin precipitate 333. In some embodiments, purifying 330 includescontacting 331 alkaline solution 332 containing dissolved lignin with awater-soluble solvent 334 to form a solid lignin precipitate 333 and analkaline solution 336 including the water-soluble solvent. In someembodiments, water soluble solvent 334 includes methanol and/or ethanoland/or acetone.

In some embodiments, precipitate 333 contains basic lignin. In someembodiments, separation 337 facilitates recycling 338 of water solublesolvent 334 and/or recycling 339 of alkali solution 318. Separation 337optionally includes evaporation (e.g. distillation) and/or coolingand/or pH adjustment.

Exemplary Lignin States

In some embodiments, lignin carries acidic phenol function(s) inprotonated form —ROH— and/or in dissociated form —RO(—). In someembodiments, lignin carries carboxylic function(s), in protonated form—RCOOH— and/or dissociated form —RCOO(—). The “acid functions” referredto here are a combination of phenol and carboxylic function which areeither in protonated or dissociated form. In some embodiments, acidiclignin is a lignin in which more than one half of the acid functions arein protonated form and basic lignin is a lignin in which more than onehalf of the acid functions are in dissociated form.

Third Exemplary Method

FIG. 36 is a simplified flow diagram of a method for processing a ligninstream indicated generally as 400. In some embodiments, feed stream 308corresponds to lignin stream 120 of FIG. 25. Method 400 is similar tomethod 300 in FIG. 35 in most respects. The main difference betweenmethod 400 and method 300 is in the way that purifying 330 is performed.This difference in purifying 330 results in different forms of lignin(i.e. 333 relative to 432).

In some embodiments of method 400 the solid lignin at 312 is acidic. Insome embodiments, cooking 320 in alkaline solution 318 produces analkaline solution 322 containing dissolved basic lignin. In someembodiments of depicted method 400, purifying 330 of basic lignin fromsolution 322 includes contacting 431 alkaline solution 322 with anacidulant 428 to produce purified acidic lignin 432. In someembodiments, a solution of HCl serves as acidulant 428. In someembodiments, acidulant 428 is added until the pH decreases to 3.7, to3.6, to 3.5 or to 3.4

In some embodiments, in purified acidic lignin 432 at least 50%, atleast 60%, at least 70%, at least 80%, at least 90% or, at least 95% ofthe acid functions are in protonated form. In some embodiments, in thebasic lignin at least 50%, at least 60%, at least 70%, at least 80%, atleast 90% or, at least 95% of the acid functions are in dissociatedform. In some embodiments, purified acidic lignin 432 is dissolved insolvent 334. In some embodiments, de-acidified lignin stream 312contains less than 2%, less than 1.5%, less than 1.0%, less than 0.5%,less than 0.3%, less than 0.2 or less than 0.1% HCl weight/weight on asis basis.

Additional Exemplary Purification Options

Referring now to both FIG. 35 and FIG. 36:

In some embodiments, purifying 330 includes contacting 331 alkalinesolution 322 with a water-soluble solvent 334 to form a basic solidlignin precipitate 333 and an alkaline solution 336 containing saidwater-soluble solvent, separating precipitate 333 and contacting 431(FIG. 36) separated basic solid lignin precipitate 333 (FIG. 35) withacidulant 428. In some embodiments, purifying 330 includes contacting431 alkaline solution 322 with acidulant 428 to form an acidic solidlignin precipitate 432. In some cases addition of alkaline solution 322is in an amount that is just sufficient to solubilize the lignin (i.e.stoichiometry). In some embodiments, purifying 330 includes contacting431 alkaline solution 322 with acidulant 428 and with alimited-solubility solvent (e.g. MEK; not depicted) to form a solventsolution containing acidic lignin 432 dissolved therein. Optionally, thesolvent is separated (e.g. by evaporation) to form a solid purifiedacidic lignin and a solvent stream to be recycled (not depicted). Insome embodiments, residual hydrocarbon (e.g. ISOPAR K) fromde-acidification 310 forms a separate phase on top of alkaline solution322 and is removed prior to contact with the limited-solubility solvent.For example, in some embodiments, lignin is decanted from the bottom ofthe cooking (320) vessel before the limited-solubility solvent is added.In some embodiments, purifying 330 includes contacting said separatedbasic (solid) lignin precipitate 333 with an acidulant 428 and with alimited-solubility solvent (not depicted) to form a solvent solutioncontaining dissolved acidic lignin 432. Optionally, thelimited-solubility solvent is separated (e.g. by evaporation) to form asolid purified acidic lignin and a solvent stream to be recycled (notdepicted).

Exemplary De-Acidification Options

In some embodiments of method 300 (FIG. 35) and method 400 (FIG. 36),de-acidifying 310 includes contacting the lignin in feed stream 308 withhydrocarbon (optionally recycled hydrocarbon) to form a de-acidifiedlignin stream 312 containing solid, optionally acidic, lignin. In someembodiments, stream 312 includes solid lignin and less than 2%, lessthan 1.5%, less than 1%, less than 0.5%, less than 0.3%, less than 0.2%or less than 0.1% weight/weight HCl on as is basis and a vapor phase 224containing HCl and water and optionally hydrocarbon. This option isdescribed hereinabove in the context of FIG. 34.

Exemplary Washing Options

In some embodiments of method 300 and method 400, the lignin in stream308 is washed with a washing HCl solution including at least 5% wt HClon as is basis to form a washed sugars solution and a washed ligninstream containing solid lignin (optionally acidic), water and HCl. Thisoption is described in the context of FIG. 34. Optionally, the washingis conducted prior to the dc-acidifying.

Exemplary Purification Variations

In some embodiments, contacting 431 of the separated basic solid ligninprecipitate with acidulant 428 includes washing with a solution ofacidulant 428. Optionally, this washing is conducted in two or morestages of contacting/431 and/or in countercurrent mode. In someembodiments, contacting 431 basic lignin precipitate with acidulant 428converts the basic lignin precipitate to acidic solid lignin 432. Insome embodiments, contacting 431 alkaline solution 322 with acidulant428 includes contacting with CO₂ under a super-atmospheric pressure. Insome embodiments, the super-atmospheric pressure is 2, 4, 6, 8 or 10 baror intermediate or greater pressure.

In some of the embodiments, contacting 431 alkaline solution 322includes contacting with acidulant 428 and with a limited-solubilitysolvent concurrently. In other embodiments, the contacting of alkalinesolution 322 with acidulant 428 is conducted prior to the contactingwith a limited-solubility solvent. In other exemplary embodiments of theinvention, the contacting of alkaline solution 322 with acidulant 428 isconducted after the contacting with the limited-solubility solvent. Insome embodiments, the limited-solubility solvent has a boiling point ofless than 150, less than 140, less than 130, less than 120 or less than110° C. at atmospheric pressure.

Exemplary Cation Removal

Referring again to FIG. 36, method 400 include removal of cations frompurified acidic lignin 432 (dissolved in limited-solubility solvent). Insome embodiments, ion exchange 440 removes cations 443 from purifiedacidic lignin 432 in the limited solubility solvent (e.g. MEK) toproduce low cation lignin 442. In some embodiments, ion exchange 440employs a strong acid cation exchange (SAC) resin (e.g. PUROLITE C150 inthe H+ form; Purolite, Bala Cynwyd, Pa., USA). Anion exchange can beviewed as part of preparing 710 (FIG. 39).

The table below summarizes cation concentrations remaining on low cationlignin 442 from two batches of lignin 432 subjected to ion exchange 440with PUROLITE C150. Batch II, which has a lower total cationconcentration, employed more resin per amount of lignin and a slowerrate of feed.

Cations associated with lignin after SAC treatment Element Batch (ppm) III Ca 400 2 K 77 <1 Mg 35 <1 Na 170 101 Si 180 93 Cu 5 2 Fe 14 104 Total881 304

Exemplary Sugar Concentrations

In some embodiments, a sugar concentration in de-acidified lignin stream312 is less than 5%, less than 4%, less than 3%, less than 2% or lessthan 1% weight/weight on as is basis. In some embodiments, a sugarconcentration in alkaline solution 322 is less than 3%, less than 2%,less than 1%, less than 0.5% or less than 0.3% weight/weight on as isbasis.

Exemplary Solvents

Some embodiments employ limited-solubility solvent. Optionally, thelimited-solubility solvent includes one or more of esters, ethers andketones with 4 to 8 carbon atoms. In some embodiments, thelimited-solubility solvent includes ethyl acetate. Optionally, thelimited-solubility solvent consists essentially of, or consists of,ethyl acetate. Some embodiments employ water soluble solvent.Optionally, the water soluble solvent includes one or more of methanol,ethanol and acetone.

Exemplary Acidulants

In some embodiments, acidulant 428 includes one or more mineral acidsand/or one or more organic acids. In some embodiments, acidulant 428includes acetic acid and/or formic acid and/or SO₂ and/or CO₂.

Additional Exemplary Method

FIG. 39 is a simplified flow diagram of a method for preparing solidlignin indicated generally as 700 according to some embodiments. Method700 includes dissolving 720 acidic lignin 722 in a limited-solubilitysolvent (e.g. MEK) and de-solventizing 730 to produce solid lignin 732.In some embodiments, acidic lignin 722 is formed by hydrolyzing 710cellulose in a lignocellulosic substrate 708 (corresponds to 112 in FIG.25) with an acid. In some embodiments, acidic lignin 722 is derived fromlignin stream 120 (FIG. 25) and includes lignin which remains aftersubstantially all of the cellulose in substrate 112 has been hydrolyzedat 110.

In some embodiments, preparing 710 includes precipitating the acidiclignin (e.g. 432 of FIG. 36) from an alkaline solution and dissolvingthe acidic lignin in the limited-solubility solvent (e.g. methyl ethylketone; MEK). In some embodiments, preparing 710 includes precipitatingbasic lignin from an alkaline solution (e.g. by contacting 331 withwater soluble solvent 334 to form ppt. 333; FIG. 27); and acidifyingbasic lignin 333 to form acidic lignin 432 and dissolving acidic lignin432 in the limited-solubility solvent. In some embodiments, preparing710 includes contacting an alkaline solution including dissolved basiclignin (e.g. 322 of FIG. 35) with an acidulant (e.g. 428 of FIG. 36) andwith a limited-solubility solvent to form a solvent solution containingdissolved acidic lignin. In some embodiments, the ratio oflimited-solubility solvent to alkaline solution 322 is between 1:3 and10:1. In some embodiments, the ratio of limited-solubility solvent toalkaline solution 322 is about 3:1. Under these conditions, contactingproduces two phases.

In some embodiments, acidulant 428 (e.g. HCl) is added to obtain a pH of3.7, to 3.6, to 3.5, to 3.4, to 3.3 or to 3.2 or intermediate pH. Insome embodiments, upon contacting 431 with a sufficient amount ofacidulant 428, the organic phase separates from the aqueous phase andlignin precipitates and partially dissolves in the limited-solubilitysolvent (e.g. MEK). In some embodiments, inorganic contaminants (e.g.ash and/or salts) dissolve in the aqueous phase.

In some embodiments, de-solventizing 720 includes contacting the acidiclignin dissolved in a limited-solubility solvent prepared at 710 with ananti-solvent (e.g. water and/or hydrocarbon(s)). In some embodiments,method 700 includes evaporation of the limited-solubility solvent. (e.g.anti-solvent is water and evaporation includes azeotropic distillationof MEK).

In some embodiments, de-solventizing 720 includes evaporating thelimited-solubility solvent. In some embodiments, evaporating of thelimited-solubility solvent includes spray drying and/or contacting witha hot liquid and/or contacting with a hot solid surface. In someembodiments, contacting with a hot solid surface produces a coating ofsolid lignin on the hot solid surface.

In some embodiments, the hot liquid has a boiling point greater thanthat of the limited-solubility solvent by at least 10° C. Examples ofsuch liquids include water, hydrocarbons and aromatic compounds.

In some embodiments, method 700 includes wet-spinning the lignin duringde-solventization 720. In some embodiments, method 700 includescontacting the lignin with a modifying reagent. In some embodiments, themodifying reagent is added to the limited-solubility solvent. In someembodiments, the modifying reagent is added to an anti-solvent used forde-solventizing. In either case, the lignin contacts the modifyingreagent when the limited-solubility solvent contacts the anti-solvent.In some embodiments, adding the modifying reagent occurs prior to orduring the de-solventization.

For example, a plasticizer (i.e. modifying reagent) is added to thelimited-solubility solvent in some embodiments of the invention. In someembodiments, the modifying reagent includes a surfactant. In someembodiments, the modifying reagent has a physical and/or a chemicalinteraction with the lignin.

In some embodiments, method 700 includes coating a solid surface withsolid lignin 722 (e.g. during de-solventizing 720). In some embodimentsof method 700 which employ spray drying for de-solventization 720, themethod includes co-spraying the lignin with a second polymer that has alinear arrangement. In some embodiments, this co-spraying contributes toformation of a rod-like assembly of resultant solid lignin 722.

Exemplary Compositions

Some embodiments relate to a lignin composition prepared by a method asdescribed hereinabove. Such a composition has at least 97% weight/weightlignin on a dry matter basis (i.e. less than 3% weight/weight non-ligninmaterial). In some embodiments, such a composition has an ash content ofless than 0.1% weight/weight and/or a total carbohydrate content of lessthan 0.05% weight/weight and/or a volatiles content of less than 5%weight/weight at 200° C. In some embodiments, the composition has anon-melting particulate content (>1 micron diameter; at 150° C.) of lessthan 0.05% weight/weight. In some embodiments, the composition includeslignin at a concentration of 97% to 99%, 97% to 99.5%, 97% to 99.9%, or98% to 99% weight/weight on a dry matter basis. In some embodiments, thelignin concentration is about 97.5%, about 98%, about 98.5%, about 99%,or about 99.5% weight/weight. In some embodiments, the ash content is0.001% to 0.1%, 0.01% to 0.1%, 0.05% to 0.1% or 0.001% to 0.05%weight/weight. In some embodiments, the ash content is about 0.1%, about0.05%, about 0.02%, about 0.01%, or about 0.005% weight/weight. In someembodiments, the volatiles content is 0.01% to 5%, 0.05% to 5%, 0.3% to5%, 0.4% to 5%, 0.5% to 5%, 1 to 5%, 0.1% to 1%, 0.1% to 2%, or 0.1% to1% weight/weight. In some embodiments, the volatiles content is about0.01%, about 0.02%, about 0.03%, about 0.04%, about 0.05%, about 0.06%,about 0.07%, about 0.08%, about 0.09%, about 0.1%, about 0.12%, about0.15%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.5%, about 2.0%, about2.5%, about 3.0%, about 4.0%, or about 5.0% weight/weight. In someembodiments, the lignin composition has a chloride content of less than500 ppm, less than 200 ppm, less than 100 ppm, less than 50 ppm, lessthan 20 ppm, less than 10 ppm, or less than 5 ppm. In some embodiments,the chloride content is about 200 ppm, about 100 ppm, about 50 ppm,about 20 ppm, about 10 ppm, about 5 ppm, or about 1 ppm. In someembodiments, the chloride content is 0.1 to 10 ppm, 1 to 20 ppm, 1 to 50ppm, or 1 to 100 ppm.

The present invention provides a lignin composition comprising: (i.e.less than 3% non-lignin material); an ash content of less than 0.1%weight/weight; a total carbohydrate content of less than 0.05%weight/weight; a volatiles content of less than 5% at 200° C.; and atleast 1 ppm of hydrocarbon of boiling point greater than 140° C., 150°C., 160° C., 170° C. or 180° C. In some embodiments, the hydrocarbonconcentration is 1 to 10 ppm, 1 to 20 ppm, 1 to 30 ppm, 1 to 40 ppm, 1to 50 ppm, 1 to 100 ppm, 1 to 1,000 ppm, 10 to 100 ppm, 20 to 100 ppm,50 to 200 ppm, 50 to 500 ppm. In some embodiments, the hydrocarbonconcentration is about 1 ppm, 5 ppm, 10 ppm, 15 ppm, 20 ppm, 25 ppm, 30ppm, 35 ppm, 40 ppm, or 50 ppm. Optionally, the composition has anon-melting particulate content (>1 micron diameter; at 150° C.) of lessthan 0.05%. In some embodiments, the non-melting particulate content is0.0001 to 0.05%, 0.001 to 0.05% or 0.01 to 0.05% weight/weight. In someembodiments, the concentration the non-melting particulate content isabout 0.001%, about 0.005%, about 0.01%, about 0.02%, about 0.03%, about0.04%, about 0.05% weight/weight.

Exemplary Thermogravimetric Profiles

FIGS. 37 and 38 present thermogravimetric profiles for lignin accordingto exemplary embodiments of the invention relative to similar profilesfor commercially available Kraft Lignin (Sigma-Aldrich; St. Louis; Mo;USA). FIG. 37 is a plot of thermo-gravimetric analysis data (TGA)indicating weight percent as a function of temperature for samples oflignin according to exemplary embodiments of the invention andconventional Kraft lignin incubated in N₂. Analysis of the derivative ofthe TGA data indicated that lignin according to tested exemplaryembodiments of the invention is stable to about 420° C. while Kraftlignin is significantly degraded at 310° C.

FIG. 38 is a plot of thermo-gravimetric analysis data (TGA) indicatingweight percent as a function of temperature for samples of lignin as inFIG. 37 incubated in air. Analysis of the derivative of the TGA dataindicated that lignin according to tested exemplary embodiments of theinvention is fully oxidized at about 420° C. while Kraft lignin chars atthis temperature.

XIV. Alternative Lignin Solubilization Embodiments

FIG. 40 is a simplified flow scheme depicting a lignocelluloseprocessing method indicated generally as method 100. Depicted method 100includes extracting 130 ash, one or more lipophilic materials, and oneor more hemicellulose sugars from a lignocellulose substrate 110 to format least one extract stream 132 and an extracted substrate 135containing cellulose and lignin. Extracting 130 ash, one or morelipophilic materials, lignin and one or more hemicellulose sugars canoccur in any order. For example, the extraction can occur sequentiallyor concurrently. In some embodiments, one or more extracted solutes isseparated from the substrate separately from one or more other extractedsolutes. Optionally, this includes two or more extractions. According tothe depicted exemplary method, extract stream 132 is separated fromextracted substrate 135.

Method 100 also includes solubilizing 140 lignin in extracted substrate135 to produce a solid cellulose composition 150 containing at least 60%cellulose on dry basis and a lignin stream 142. In some embodimentssolid cellulose composition 150 includes 70%, 80%, 90%, or even 95% ormore cellulose. In some embodiments, solubilizing 140 includescontacting with an alkaline solution (e.g. pH≧9.0) and/or an organicsolvent and/or a base and/or a super-critical solvent and/or asulfonation agent and/or an oxidizing agent.

Method 100 also includes hydrolyzing 160 solid cellulose composition 150with an acid to form a hydrolysate 162 including soluble sugars and theacid and de-acidifying 170 hydrolysate 162 to form a de-acidified sugarsolution 172. In some embodiments, hydrolyzing 160 is performed in avessel and at least 90% of available sugars in solid cellulosecomposition 150 have a residence time in the vessel ≦16 hours.

In some embodiments, a chemical reaction which increases extractabilityof one or more solutes in the substrate is conducted prior to, orconcurrent with, the extraction. For example, lignin may be reacted witha sulfonating agent or an oxidizing agent to solubilize it and make itmore extractable. In some embodiments, extraction conditions may beadjusted to increase solubility of one or more potential solutes in thesubstrate. Extraction conditions that can be altered to increasesolubility of a potential solute include temperature, degree ofoxidation and pH. In some embodiments, the substrate is treatedmechanically (e.g. by grinding or comminution) to increase transfer rateof one or more potential solutes into an applied solvent (extractionliquid). In some embodiments, the substrate is chemically modified torender one or more substrate components more soluble under theextraction conditions.

In some embodiments, extraction includes removal of monomeric oroligomeric subunits released from polymers as solutes. For example,hemicellulose consists primarily of water insoluble polymeric sugarswhich have a solubility of 1% or less in water at 100° C. However, underappropriate conditions, depolymerization releases sugars with asolubility of more than 1% in water at 100° C. (e.g. monomers such asxylose, mannose, or arabinoses; oligomers containing one or more ofthese monomers). Lipohilic material includes fatty, water insolublecompounds, for example tall oils, pitch and resins, terpenes, and othervolatile organic compounds.

In some embodiments, extraction 130 extracts one or more proteinaceousmaterials. In some embodiments, extraction 130 removes pectin oroligomers of galactauronic acid from the substrate. In some embodiments,the extracting includes a single extraction 130 which produces a singleextract stream 132. In other embodiments, the extracting includes two ormore extractions 130 which produce two or more extract streams 132. Insome embodiments, a single extraction is conducted in multiple stages.In some embodiments, hydrolysis 160 employs HCl as a catalyst.Optionally, hydrolyzing 160 includes contacting solid cellulosecomposition 150 with an HCl solution wherein HCl/(HCl+H2O) is at least25, 30%, 35%, 37%, 39% or at least 41% weight/weight. In someembodiments, the lignin content of hydrolysate 162 is in an amount up to5%, 4%, 3%, 2% or 1% weight/weight. Optionally, hydrolysate 162 isessentially free of lignin. In some embodiments, the solids content ofhydrolysate 162 is in an amount up to 5%, 4%, 3%, 2% or 1%. Optionally,hydrolysate 162 is essentially free of solids. In some embodiments,de-acidifying 170 includes contacting with an S1 solvent. Optionally,the S1 solvent includes hexanol and/or 2-ethyl hexanol.

In some embodiments, method 100 includes applying a predeterminedpressure-temperature-time profile (PPTTP) 108 to lignocellulosesubstrate 110. In some embodiments, PPTTP 108 is characterized by aseverity factor of at least 3, 3.2, 3.4, 3.6, 3.8, or 4.0. In someembodiments, PPTTP 108 is characterized by a severity factor of lessthan 5, 4.8, 4.6, 4.4 or 4.2. Optionally, PPTTP 108 is characterized bya severity factor of 3.4 to 4.2, optionally 3.6 to 4.0, optionally 3.8to 24.

Exemplary Extraction Conditions

In some embodiments, extracting 130 includes hydrolyzing polysaccharides(not to be confused with hydrolysis 160) in substrate 110 and removingformed water-soluble polysaccharides. Optionally, the removing includeswashing and/or pressing. In some embodiments, a moisture content ofsubstrate 110 is at least 40%, at least 50% or at least 60% during boththis hydrolyzing and the removing.

In some embodiments, during both this hydrolyzing and the removing atemperature of the substrate is at least 50° C., at least 60° C., atleast 70° C., at least 80° C. or at least 90° C.

In some embodiments, this hydrolyzing is conducted at a temperaturegreater than 100° C. and the removing is conducted at a temperaturelower than 100° C. In some embodiments, this hydrolyzing is conducted ata super-atmospheric pressure and the removing is conducted atatmospheric pressure. Optionally, the removing includes washing with asolution of an acid. In some embodiments, the acid includes sulfuricand/or sulfurous acid. In those embodiments employing sulfuric acid, theconcentration is optionally 5% or less.

In some embodiments, extracting 130 includes contacting with anextractant containing a water-soluble organic solvent. Examples ofsuitable water soluble organic solvents include to alcohols and ketones.In some embodiments, the solvent includes acetone. Optionally, thesolvent includes a weak acid such as sulfurous acid, acetic acid orphosphorous acid. In some embodiments, extracting 130 includescontacting with an alkaline solution (pH≧9.0) and/or an organic solventand/or a base and/or a super-critical solvent and/or a sulfonation agentand/or an oxidizing agent. In some embodiments, extracting 130 involvescontacting substrate 110 with a solvent at an elevated temperature. Insome embodiments, extracting 130 involves contacting with an alkali oralkaline solution at an elevated temperature. In some embodiments,extracting 130 involves oxidation and/or sulfonation and/or contactingwith a reactive fluid. Various methods for extracting 130 are describedin Carvalheiro et al. (2008; Journal of Scientific & Industrial Research67:849-864); E. Muurinen (Dissertation entitled: “Organosolv pulping: Areview and distillation study related to peroxyacid pulping” (2000)Department of Process Engineering, Oulu University, Finland) and Bizzariet al. (CEH Marketing research report: Lignosulfonates (2009) pp.14-16).

Exemplary Extracted Substrate Characteristics

In some embodiments, a ratio of cellulose to lignin in extractedsubstrate 135 is greater than 0.6, greater than 0.7 or even greater than0.8. In some embodiments, extracted substrate 135 includes ≦0.5% ash. Insome embodiments, extracted substrate 135 includes ≦70 PPM sulfur. Insome embodiments, extracted substrate 135 includes ≦5% solublecarbohydrate. In some embodiments, extracted substrate 135 includes≦0.5% tall oils.

Exemplary Solid Cellulose Composition Characteristics

In some embodiments, solid cellulose composition 150 includes at least80%, 85%, 90%, 95%, or 98% cellulose on a dry matter basis. In someembodiments, the cellulose in solid cellulose composition 150 is atleast 40%, 50%, 60%, 70% or 80% crystalline. In some embodiments, lessthan 50%, 40%, 30% or 20% of the cellulose in solid cellulosecomposition 150 is crystalline cellulose.

In some embodiments, solid cellulose composition 150 includes at least85%, 90%, 95% or 98% of the cellulose in lignocellulose substrate 110.In some embodiments, solid cellulose composition 150 includes less than50%, less than 60%, less 70% or less than 80% of the ash inlignocellulose substrate 110. In some embodiments, solid cellulosecomposition 150 includes less than 50%, less than 60%, less 70% or lessthan 80% of the calcium ions in lignocellulose substrate 110. In someembodiments, solid cellulose composition 150 includes less than 30% 20%,10% or even less than 5% weight/weight of the lipophilic materials inlignocellulose substrate 110. In some embodiments, solid cellulosecomposition 150 includes in an amount up to 30% 20%, 10% or 5%weight/weight of the lignin in lignocellulose substrate 110. In someembodiments, solid cellulose composition 150 includes water-solublecarbohydrates at a concentration of less than 10% wt, 8% wt, 6% wt, 4%wt, 2% wt, or 1% wt. In some embodiments, solid cellulose composition150 includes acetic acid in an amount ≦50%, ≦40%, ≦30 or even ≦20%weight/weight of the acetate function in 110.

In some embodiments, lignocellulose substrate 110 includes pectin.Optionally, solid cellulose composition 150 includes less than 50%, 40%,30%, or 20% weight/weight of the pectin in substrate 110. In someembodiments, lignocellulose substrate 110 includes divalent cations.Optionally, solid cellulose composition 150 includes less than 50%, 40%,30%, or 20% weight/weight of divalent cations present in substrate 110.

Exemplary Acid Hydrolysis Parameters

In some embodiments, acid hydrolysis 160 is performed in a vessel and≦99% of solid cellulose composition 150 is removed from the vessel ashydrolysate 162 while ≧1% of solid cellulose composition 150 is removedas residual solids. Exemplary vessel configurations suitable for use inthese embodiments are described in co-pending PCT applicationUS2011/57552 (incorporated by reference herein for all purposes). Insome embodiments, the vessel employs a trickling bed. Optionally, thereis essentially no solids removal from the bottom of the vessel. In someembodiments, the vessel has no drain.

In some embodiments, at least 90% of available sugars in solid cellulosecomposition 150 have a residence time in vessel ≦16 hours; ≦14; ≦12;≦10≦15 or even ≦2 hours.

Exemplary Hemicellulose Stream Characteristics

In some embodiments, extracting 130 produces a hemicellulose sugarstream (depicted as extract stream 132) characterized by a purity of atleast 90%, at least 92%, at least 94%, at least 96% or at least 97%weight/weight on a dry matter basis.

In some embodiments, the hemicellulose sugar stream has a w/w ratio ofsugars to hydroxymethylfurfural greater than 10:1, greater than 15:1 orgreater than 20:1. In some embodiments, the hemicellulose sugar streamhas hydroxymethylfurfural content of less than 100 PPM. 75 PPM, 50 PPMHor even less than 25 PPM.

Optionally, the hemicellulose sugar stream includes soluble fibers.

In some embodiments, the hemicellulose sugar stream includes acetic acidin an amount equivalent to at least 50%, at least 60%, at least 70% oreven at least 80% weight/weight of the acetate function in substrate110.

In some embodiments, substrate 110 includes pectin and the hemicellulosesugar stream includes methanol in an amount equivalent to at least 50%,at least 60%, at least 70% or at least 80% weight/weight of the methanolin the pectin.

In some embodiments, the hemicellulose sugar stream includes divalentcations in an amount equivalent to at least 50%, at least 60%, at least70%, at least or even %, at least 80% weight/weight of their content in110.

Exemplary Sugar Conversion

In some embodiments, method 100 (FIG. 40) includes fermenting 180de-acidified sugar solution 172 to produce a conversion product 182. Inother embodiments, method 100 (FIG. 40) includes subjecting de-acidifiedsugar solution 172 to a non-biological process 181 to produce aconversion product 182. Exemplary non-biological processes includepyrolysis, gasification and “bioforming” or “aqueous phase reforming(APR)” as described by Blommel and Cartwright in a white paper entitled“Production of Conventional Liquid Fuels from Sugars” (2008) as well asin U.S. Pat. No. 6,699,457; U.S. Pat. No. 6,953,873; U.S. Pat. No.6,964,757; U.S. Pat. No. 6,964,758; U.S. Pat. No. 7,618,612 andPCT/US2006/048030; (incorporated by reference herein for all purposes).

In some embodiments, method 100 includes processing 190 conversionproduct 182 to produce a consumer product 192 selected from the groupconsisting of detergent, polyethylene-based products,polypropylene-based products, polyolefin-based products, polylactic acid(polylactide)-based products, polyhydroxyalkanoate-based products andpolyacrylic-based products.

In some embodiments, detergent contains a sugar-based surfactant, afatty acid-based surfactant, a fatty alcohol-based surfactant, or acell-culture derived enzyme. In some embodiments, a polyacrylic-basedproduct is selected from plastics, floor polishes, carpets, paints,coatings, adhesives, dispersions, flocculants, elastomers, acrylicglass, absorbent articles, incontinence pads, sanitary napkins, femininehygiene products, and diapers. In some embodiments, polyolefin-basedproducts are selected from milk jugs, detergent bottles, margarine tubs,garbage containers, water pipes, absorbent articles, diapers, nonwovens,HDPE toys and HDPE detergent packaging. In some embodiments,polypropylene based products are selected from absorbent articles,diapers and nonwovens. In some embodiments, polylactic acid basedproducts are selected from packaging of agriculture products and ofdairy products, plastic bottles, biodegradable products and disposables.In some embodiments, polyhydroxyalkanoate based products are selectedfrom packaging of agriculture products, plastic bottles, coated papers,molded or extruded articles, feminine hygiene products, tamponapplicators, absorbent articles, disposable nonwovens and wipes, medicalsurgical garments, adhesives, elastomers, films, coatings, aqueousdispersants, fibers, intermediates of pharmaceuticals and binders. Inother exemplary embodiments of the invention, conversion product 182includes at least one member of the group consisting of ethanol,butanol, isobutanol, a fatty acid, a fatty acid ester, a fatty alcoholand biodiesel.

According to these embodiments, method 100 can include processing 190 ofconversion product 182 to produce at least one consumer product 192selected from the group consisting of an isobutene condensation product,jet fuel, gasoline, gasohol, diesel fuel, drop-in fuel, diesel fueladditive, and a precursor thereof. In some embodiments, gasahol isethanol-enriched gasoline or butanol-enriched gasoline. In someembodiments, consumer product 192 is selected from the group consistingof diesel fuel, gasoline, jet fuel and drop-in fuels.

Exemplary Consumer Products from Sugars

The present invention also provides a consumer product 192, a precursorof a consumer product 192, or an ingredient of a consumer product 192produced from conversion product 182. Examples of such consumer products192, precursor of a consumer products 192, and ingredients of a consumerproduct 192 include at least one conversion product 182 selected fromcarboxylic and fatty acids, dicarboxylic acids, hydroxylcarboxylicacids, hydroxyldicarboxylic acids, hydroxyl-fatty acids, methylglyoxal,mono-, di-, or poly-alcohols, alkanes, alkenes, aromatics, aldehydes,ketones, esters, biopolymers, proteins, peptides, amino acids, vitamins,antibiotics, and pharmaceuticals.

In some embodiments, consumer product 192 is ethanol-enriched gasoline,jet fuel, or biodiesel. Optionally, consumer product 192, or itsprecursor precursor of a consumer product, or an ingredient of thereofhas a ratio of carbon-14 to carbon-12 of about 2.0×10⁻¹³ or greater. Insome embodiments, consumer product 192 includes an ingredient asdescribed above and an additional ingredient produced from a rawmaterial other than lignocellulosic material. In some embodiments, theingredient and the additional ingredient produced from a raw materialother than lignocellulosic material are essentially of the same chemicalcomposition. In some embodiments, consumer product includes 192 a markermolecule at a concentration of at least 100 ppb. In some embodiments,the marker molecule is selected from the group consisting of furfural,hydroxymethylfurfural, products of furfural or hydroxymethylfurfuralcondensation, color compounds derived from sugar caramelization,levulinic acid, acetic acid, methanol, galcturonic acid, and glycerol.

In some embodiments, solubilizing 140 produces a lignin stream 142.

Exemplary Lignin Stream Characteristics

FIG. 41 is a simplified flow scheme of a method for processing a ligninstream indicated generally as method 200. In depicted embodiment 200,lignin stream 208 corresponds to lignin stream 142 of FIG. 40.

In some embodiments, lignin stream 208 is characterized by a purity ofleast 90 92%, 94%, 96% or 97% weight/weight or more. Purity of ligninstream 208 is measured on a solvent free basis. In some embodiments, thesolvent includes water and/or an organic solvent. Concentrations ofimpurities in lignin stream 208 are on as is basis. In some embodiments,lignin stream 208 includes chloride (Cl) content in an amount up to0.5%, 0.4%, 0.3%, 0.2%, 0.1 or 0.05% weight/weight. In some embodiments,lignin stream 208 includes ash content in an amount up to 0.5%, 0.4%,0.3%, 0.2%, or 0.1% weight/weight. In some embodiments, lignin stream208 includes phosphorus at a concentration of less than 100 PPM, lessthan 50 PPM, less than 25 PPM, less than 10 PPM, less than 1 PPM, lessthan 0.1 PPM, or less than 0.01 PPM. In some embodiments, lignin stream208 includes a soluble carbohydrate content in an amount up to 5%, 3%,2%, or 1% weight/weight. In some embodiments, lignin stream 208 includesone or more furfurals at a total concentration of at least 10 PPM, atleast 25 PPM, at least 50 PPM, or even at least 100 PPM. In someembodiments, lignin stream 208 includes ≦0.3%, ≦0.2% or ≦0.1%weight/weight divalent cations. In some embodiments, lignin stream 208includes ≦0.07%, ≦0.05% or ≦0.03% weight/weight sulfur. In someembodiments, lignin stream 208 includes lignin in solution and/or asuspension of solid lignin in a liquid. In some embodiments, the liquidincludes water and/or an organic solvent. Alternatively, lignin stream208 can be provided as a wet solid or a dry solid. In those embodimentsincluding lignin in solution, the lignin concentration can be greaterthan 10%, 20%, 30% or greater than 40% weight/weight.

Exemplary Lignin Conversion Method

Referring again to FIG. 41, in some embodiments, method 200 includesconverting 210 at least a portion of lignin in lignin stream 208 to aconversion product 212. In some embodiments, converting 210 employsdepolymerization, oxidation, reduction, precipitation (by neutralizationof the solution and/or by solvent removal), pyrolysis, hydrogenolysis,gasification, or sulfonation. In some embodiments, conversion 210 isoptionally conducted on lignin while in solution, or afterprecipitation. In some embodiments, converting 210 includes treatinglignin with hydrogen. In some embodiments, converting 210 includesproducing hydrogen from lignin.

In some embodiments, conversion product 212 includes at least one itemselected from the group consisting of bio-oil, carboxylic and fattyacids, dicarboxylic acids, hydroxylcarboxylic, hydroxyldicarboxylicacids and hydroxyl-fatty acids, methylglyoxal, mono-, di- orpoly-alcohols, alkanes, alkenes, aromatics, aldehydes, ketones, esters,phenols, toluenes, and xylenes. In some embodiments, the conversionproduct includes a fuel or a fuel ingredient. Optionally, the conversionproduct includes para-xylene.

In some embodiments, converting 210 includes aqueous phase reforming. Insome embodiments, converting 210 includes at least one bioformingreaction. Exemplary bioforming reaction types include catalytichydrotreating and catalytic condensation, zeolite (e.g. ZSM-5) acidcondensation, base catalyzed condensation, hydrogenation, dehydration,alkene oligomerization and alkylation (alkene saturation). In someembodiments, the converting occurs in at least two stages (e.g. 210 and220) which produce conversion products 212 and 222 respectively.Optionally, a first stage (210) includes aqueous phase reforming. Insome embodiments, second stage 220 includes at least one of catalytichydrotreating and catalytic condensation.

Optionally, method 200 is characterized by a hydrogen consumption ofless than 0.07 ton per ton of product 212 and/or 222.

Exemplary Lignin Products

The present invention also provides a consumer product, a precursor of aconsumer product or an ingredient of a consumer product produced from alignin stream 208. In some embodiments, the consumer product ischaracterized by an ash content of less than 0.5% wt and/or by acarbohydrates content of less than 0.5% wt and/or by a sulfur content ofless than 0.1% wt and/or by an extractives content of less than 0.5% wt.In some embodiments, the consumer product produced from lignin stream208 includes one or more of bio-oil, carboxylic and fatty acids,dicarboxylic acids, hydroxylcarboxylic, hydroxyldicarboxylic acids andhydroxyl-fatty acids, methylglyoxal, mono-, di- or poly-alcohols,alkanes, alkenes, aromatics, aldehydes, ketones, esters, biopolymers,proteins, peptides, amino acids, vitamins, antibiotics, andpharmaceuticals. In some embodiments, the consumer product includes oneor more of dispersants, emulsifiers, complexants, flocculants,agglomerants, pelletizing additives, resins, carbon fibers, activecarbon, antioxidants, liquid fuel, aromatic chemicals, vanillin,adhesives, binders, absorbents, toxin binders, foams, coatings, films,rubbers and elastomers, sequestrants, fuels, and expanders. In someembodiments, the product is used in an area selected from the groupconsisting of food, feed, materials, agriculture, transportation andconstruction. Optionally, the consumer product has a ratio of carbon-14to carbon-12 of about 2.0×10⁻¹³ or greater.

Some embodiments relate to a consumer product containing an ingredientas described above and an ingredient produced from a raw material otherthan lignocellulosic material. In some embodiments, the ingredient andthe ingredient produced from a raw material other than lignocellulosicmaterial are essentially of the same chemical composition.

In some embodiments, the consumer product includes a marker molecule ata concentration of at least 100 ppb. In some embodiments, the markermolecule is selected from the group consisting of furfural andhydroxymethylfurfural, products of their condensation, color compounds,acetic acid, methanol, galactauronic acid, glycerol, fatty acids andresin acids.

In some embodiments, the product is selected from the group consistingof dispersants, emulsifiers, complexants, flocculants, agglomerants,pelletizing additives, resins, carbon fibers, active carbon,antioxidants, liquid fuel, aromatic chemicals, vanillin, adhesives,binders, absorbents, toxin binders, foams, coatings, films, rubbers andelastomers, sequestrants, fuels, and expanders.

EXAMPLES

It is understood that the examples and embodiments described herein arefor illustrative purposes only and are not intended to limit the scopeof the claimed invention. It is also understood that variousmodifications or changes in light the examples and embodiments describedherein will be suggested to persons skilled in the art and are to beincluded within the spirit and purview of this application and scope ofthe appended claims. All publications, patents, and patent applicationscited herein are hereby incorporated by reference in their entirety forall purposes.

Example 1 Small Scale Hemicellulose Sugar Extraction

Table 1 provides a summary of chemical analysis of the liquor resultingfrom hemicellulose sugar extraction of various biomass types. The %monomeric sugar is expressed as % weight out of total sugars weight. Allother results are expressed as % weight relative to dry biomass.

All treatments were carried out in a 0.5 L pressure reactor equippedwith a stirrer and heating-cooling system. The reactor was charged withthe biomass and the liquid at amounts given in the table. The reactorwas heated to the temperature indicated in the table, time count wasstarted once the reactor reached 5° C. below the designated temperature.Once the time elapsed, the reactor was cooled down. Solid and liquidwere separated, and the content of the obtained liquor was analyzed, alldata was back calculated relative to dry biomass weight. HPLC methodswere applied to evaluate % Total Sugars in the liquor, % monomericsugars and % Acetic Acid. The % Degradation product is the sum of %Furfurals (GC or HPLC analysis), % Formic acid (HPLC) and % Levullinicacid (HPLC). Acid Soluble Lignin was analyzed according to NRELTP-510-42627 method.

TABLE 1 Treatment conditions and chemical analysis of the resultingliquor Biomass Acid % Degradation Biomass Dry Soln. (s) con. Time, %TS¹/ % DP1³/ % AcOH⁴/ Products⁵/ % ASL/ Ref# Type wt, g wt. % wt T ° C.min DB² % TS DB DB DB 9114 Eucalyptus 45.2 198.2 0.7⁶ 140 40 22.4 NA 1.7NA NA   5a Eucalyptus 33.2 199.5 0.7⁶ 135  90 60  60 21.8 91 3.6 1.3 3.59004 Acacia 33.7 201.8 0.7⁶ 145 40 21.2 79 3.3 0.9 2.6 9012 Leucaena34.1 201.3 0.7⁶ 145 60 22.0 96 3.4 1.3 2.0 9018 EFB 34.6 203.8 0.7⁶ 14540 25.2 79 1.3 0.7 1.2 9019 Bagasse 13.3 194.8 0.7⁶ 145 40 29.8 96 2.50.7 2.5 YIITp83/15 Pine 18.1 190.5 0.7⁷ 160 15 22.9 95 0.07 1.5 0.9 ¹%Total Sugars (% TS) measured by HPLC in the liquor ²DB—Dry Biomass ³%Monomers out of total dissolved sugars measured by HPLC in the liquor ⁴%Acetic Acid measured by HPLC in the liquor ⁵% Degradation Products = %Furfurals + % Formic Acid + % Levullinic Acid. % Furfurals measured byGC or HPLC, % Formic acid and % Levullinic acid measured by HPLC ⁶0.5%H₂SO₄ + 0.2% SO₂ ⁷0.7% H₂SO₄ + 0.03% Acetic acid

Example 2 Large Scale Chemical Analysis of Lignocellulose Matter afterHemicellulose Sugar Extraction

Table 2 provides a summary of chemical analysis of various types ofbiomass after hemicellulose sugar extraction.

Pine (ref A1202102-5): Fresh Loblloly pine chips (145.9 Lb dry wood)were fed into a Rapid Cycle Digester (RDC, Andritz, Springfield, Ohio.An acid aqueous solution (500 Lb) was prepared by adding 0.3% H2SO4 and0.2% S02 to water in a separate tank. The solution was heated to 135 Cand then added to the digester to cover the wood. The solution wascirculated through the wood for 40 minutes while maintaining thetemperature. After 60 minutes, the resulting liquor was drained to aliquor tank and using steam the wood was blown to a cyclone to collectthe wood (128.3 Lb dry wood) and vent the vapor. The extracted wood wasanalyzed for sugar content, carbohydrate composition, ash, elements (byICP), and DCM extractives. The analyses of the hemi depletedlignocellulose material show extraction of 42.4% Arabinan, 10.5%Galactan, 9.6% Xylan, 14.3% Manan, and 11.8% Glucan, indicating thatmostly hemicellulose is extracted. Analyses also show 11.6% of “others”,including ASL, extractives and ash. The overall fraction ofcarbohydrates in the remaining solid is not different within the errorof the measurement to that of the starting biomass due to this removalof “others”. It is however easily notices that the extracted woodchipsare darker in color and are more brittle than the fresh biomass.

Pine (ref A1204131-14(K1)): Fresh Loblloly pine chips (145.9 Lb drywood) were fed into a Rapid Cycle Digester (RDC, Andritz, Springfield,Ohio. An acid aqueous solution (500 Lb) was prepared by adding 0.3%H2SO4 and 0.2% S02 to water in a separate tank. The solution was heatedto 135 C and then added to digester to cover the wood. The solution wascirculated through the wood for 180 minutes while maintaining thetemperature. After 180 minutes, the resulting liquor was drained to aliquor tank and using steam the wood was blown to a cyclone to collectthe wood (121.6 Lb dry wood) and vent the vapor. The material wasanalyzed as described above. The analyses of the hemi depletedlignocellulose material show extraction of 83.9% Arabinan, 84.3%Galactan, 50.1% Xylan, 59.8% Manan and no extraction of glucan,indicating effective extraction of hemicellulose. Analyses also showextraction of 21.8% of “others” including lignin, extractives and ash.

Eucalyptus (ref A120702K6-9): Fresh Eucalyptus Globulus chips (79.1 Kgdry wood) were fed into a Rapid Cycle Digester (RDC, Andritz,Springfield, Ohio). An acid aqueous solution was prepared by adding 0.5%H2SO4 and 0.2% S02 to water in a separate tank. The solution was heatedto 145 C and then added to digester to cover the wood. The solution wascirculated through the wood for 60 minutes while maintaining thetemperature, then heating was stopped while circulation continued foranother 60 minute, allowing the solution to cool. After 120 minutes, theresulting liquor was drained to a liquor tank and using steam the woodwas blown to a cyclone to collect the wood (58.8 Kg dry wood) and ventthe vapor. The material was analyzed as described above. Analyses showedthat 20.1% of the carbohydrates were extracted from the wood (dry woodbase) xylose containing 70% of these sugars, 91% of the sugars in theliquor present as monomers. Under these conditions acetic acidconcentration in the liquor was 3.6% (dry wood base) showing maximalremoval of acetate groups from hemicellulose sugars; 4.2% (dry woodbase) of acid soluble lignin. These results indicate effectiveextraction of hemicellulose and in particularly xylose, along withhydrolysis of the acetate groups from substituted xylosans. At the sametime a significant amount of acid soluble lignin, extractives and ashare also extracted into the liquor.

TABLE 2 Chemical analysis of lignocellulose matter after hemicellulosesugar extraction % Total DCM Biomass Ash Ca Na Mg K % % % % % Carbo-Extrac- Ref Type % wt ppm ppm ppm ppm Arabinan Galactan Glucan XylanMannan hydrate tives A1202102- Pine 0.59 248 NA 123 92 0.25 1.33 48.134.75 8.48 62.94 NA 5¹ A1204131- Pine 0.31 113 388 44 23 0.21 0.38 51.683.14 4.89 60.30 1.07 14(K1)² A120702K6- Eucalyptus 0.35 95 109 30 72<0.01 0.03 67.48 2.13 0.20 69.54 0.26 9³ ¹Hemicellulose sugarextraction: 135° C. for 60 minutes, 0.3% H₂S0₄, 0.2% S0₂. ²Hemicellulosesugar extraction: 135° C. for 180 minutes, 0.3% H₂S0₄, 0.2% S0₂.³Hemicellulose sugar extraction: 145° C. for 60 minutes + cool down 60minutes, 0.3% H2S04, 0.2% S0₂.

Example 3 Aqueous and Organic Streams Resulting from Amine Extractionwith Hardwood

The acidic hemicellulose sugar stream resulting from hemicellulose sugarextraction of Eucalyptus chips (as exemplified in Example 2) was used inthis small scale experiment. The aqueous stream before the extractionwas prepared by extracting eucalyptus in a solution containing 0.5%H₂SO₄ and 0.2% SO₂, separating the liquid from the solid, and contactingthe liquid with a strong cation exchange resin. The results providedwere obtained in a batch experiment, where the organic phase (amineextractant; tri-laurylamine:hexanol ratio 3:7) to aqueous phase(hemicellulose sugar stream) ratio was 4:1, contact time 15 minutes at60° C. A highly efficient extraction of sulfuric acid and acetic acid isobserved, along with good extraction of acid soluble lignin (75%) andminimal loss of sugars (2%) into the organic phase.

Table 3 provides chemical analysis of the aqueous stream before andafter the amine extraction, expressed as % weight of the aqueoussolution.

TABLE 3 Chemical composition of the aqueous stream before and afteramine extraction Aqueous Stream Before Amine Aqueous Stream After SoluteExtraction Amine Extraction % Extracted % Acetic acid 0.856 0.017 98 %Sulfuric acid 0.5131 0.0001 100 % Total sugar 5.07 4.97 2 % ASL 0.250.063 75 % 2-Furfural 0.041 0.003 93 % HMF 0.0007 0.0000 98

Example 4 Back Extraction of the Acid from the Amine Extractant

The amine extractant of Example 3 was contacted with a 1% sodiumcarbonate solution at a 1:1 ratio for 15 minutes at 60° C. It wasobserved that 84% of the acetic acid and 89% of the sulfuric acid wereback extracted from the amine extractant organic phase. Organic acidscan be recovered from the back extraction. Alternatively, the backextraction can be diverted to waste treatment. Table 4 summarizes theacid concentrations in the amine extractant before and after the backextraction.

TABLE 4 Mineral acid and acetic acid concentration in the organic streambefore and after back extraction Amine extractant Amine extractantbefore back after back parameters extraction extraction % acetic acid0.213 0.035 % sulfuric acid 0.128 0.014

Example 5 Eucalyptus Sugar Composition

Eucalyptus sugar composition (DH2C001): Eucalyptus Globulus chips wereextracted by treating about 1200 Lb wood (dry base) with an aqueoussolution containing 0.5% H₂SO₄ and 0.2% SO₂, at a ratio of 2.66 liquidto solid in an agitated, temperature controlled tank at averagetemperature of 130-135° C. for 3 hours. The collected liquor wascollected, the chips were washed with water, the wash water was thenused to prepare the acid solution of the next batch by adding acids asneeded. The hemicellulose-depleted chips were then milled to ˜1400micron and dried to ˜15% moisture.

The acidic hemicellulose sugar stream ran through a SAC column. Thesugar stream was then extracted batchwise for two times with anextractant having tri-laurylamine:hexanol at a ratio of 30:70. Theextractant to sugar stream ratio 2:1. The resulting aqueous phase wasfurther purified by using a SAC column, a WBA resin and a mixed bedresin. The pH of the resulting stream was adjusted to 4.5 with 0.5% HCland the sugar solution was evaporated to final concentration of ˜70% DS.

The resulting hemicellulose sugar mixture was evaporated to a totalsugar concentration of 70-80%, to render it osmotically stable. Table 5Aprovides a chemical analysis of the resulting hemicellulose sugarmixture.

TABLE 5A Chemical analysis of a hemicellulose sugar mixture produced byhemicellulose sugar extraction and purification of eucalyptus chipsPARAMETER RESULT UNITS APPEARANCE Colorless pH 3.13 Saccharides DS(HPLC) 72.37 % wt/wt % Total monosaccharides 91.71 DS/DS (w/w)Composition (HPAE-PAD) XYLOSE 67.23 (48.65) DS/DS (w/w) ARABINOSE 3.09(2.24) DS/DS (w/w) MANNOSE 5.83 (4.22) DS/DS (w/w) GLUCOSE 4.64 (3.36)DS/DS (w/w) GALACTOSE 8.22 (5.95) DS/DS (w/w) FRUCTOSE 3.40 (2.46) DS/DS(w/w) Impurities Furfurals (UV) 0.0005 % wt/wt Phenols (FC) 0.047 %wt/wt Metals & inorganics (ICP) Ca <2 ppm Cu <2 ppm Fe <2 ppm K <2 ppmMg <2 ppm Mn <2 ppm Na 22 ppm S 6.7 ppm P 4.2 ppm

Bagasse sugar composition (DB4D01): Baggase was shredded in a woodshredder. In a temperature controlled tank, 60 Lb bagasse (dry base) wasthen treated with an aqueous solution containing 0.5% H₂SO₄, at a liquidto solid ratio of 14.2. The average temperature of the temperaturecontrolled tank was maintained at 130-135° C. for 3 hours. The solutionwas circulated by pumping. The resulting liquor was collected, and thesolids were washed with water. The wash water was then used to preparethe acid solution for the next batch by adding acids as needed. Thehemicellulose-depleted lignocellulosic matter was collected and dried.

The acidic hemicellulose sugar stream ran through a SAC column. Thesugar stream was then extracted continuously in a series of mixersettlers (2 stages) with an extractant having tri-laurylamine:hexanol ata ratio of 30:70. The extractant to sugar stream ratio was kept in therange of 2:1 to 1.5:1. The resulting aqueous phase was further purifiedby using a SAC resin, a WBA resin, a granulated active carbon and amixed bed resin. The pH of the resulting stream was adjusted to 4.5 with0.5% HCl and the sugar solution was evaporated to a concentration of˜30% DS. The resulting sugar stream contains about 7% arabinose, 2.5%galactose, 6.5% glucose, 65% xylose, 1.5% mannose, 4% fructose and 14%oligosaccharides (all % weight/total sugars). This sugar solution wasfurther processed by fractionation on an SSMB system, resulting in axylose rich fraction and a xylose depleted fraction. Each fraction wasconcentrated by evaporation. Table 5B provides a chemical analysis ofthe resulting xylose rich sugar solution.

TABLE 5B Chemical analysis of a hemicellulose sugar mixture produced byhemicellulose sugar extraction and purification of bagasse PARAMETERRESULT UNITS APPEARANCE Colorless pH 3.58 Saccharides % TS (HPLC) 68.2 %w/w Composition (HPAE-PAD) XYLOSE 81.84 (55.81) %/TS (% w/w) ARABINOSE4.38 (2.99) %/TS (% w/w) MANNOSE 1.99 (1.36) %/TS (% w/w) GLUCOSE 5.07(3.46) %/TS (% w/w) GALACTOSE 0.91 (0.62) %/TS (% w/w) FRUCTOSE 6.15(4.20) %/TS (% w/w) Impurities Furfurals (GC) <0.005 % w/w Phenols (FC)0.04 % w/w Metals & inorganics (TCP) Ca <2 ppm Cu <2 ppm Fe <2 ppm K <2ppm Mg <2 ppm Mn <2 ppm Na <2 ppm S <10 ppm P <10 ppm

Example 6 Fractionation of Xylose from Hemicellulose Sugar Mixture

Xylose was fractionated from hemicellulose sugar mixture containing 17%weight/weight glucose, 71% weight/weight xylose, 7% weight/weightarabinose, 0.3% weight/weight galactose, 0.2% weight/weight mannose, and5% weight/weight mixed dimeric saccharides. The composition of thismixture is representative for hemicellulose sugar compositions fromhardwood chips (e.g., Eucalyptus chips) and some grasses (e.g.,bagasse).

A pulse test was conducted utilizing 250 ml of Finex AS 510 GC, Type I,SBA, gel form, styrene divinylbenzene copolymer, functional grouptrimethylamine, specific gravity 1.1-1.4 g/cm³, mean bead size 280millimicrons. The gel was in the sulfate form. It was pre-conditionedwith 1.5 bed volume (BV) of 60 mM OH⁻, adjusting the resin to 8-12% OHand leaving the remainder in the sulfate form. A 5 ml sample wasinjected, followed by water elution at 3 ml/min. Effective fractionationof xylose from the mixture was observed, with the mix sugars peaking at0.61 and 0.65 BV, and xylose peaking at 0.7 BV. The pulse test resultsare described in FIG. 7.

In a pulse test, a column was loaded with a sample, and washed with aneluent. Elution fractions were collected and analyzed. For differentsugars, the elution resulted in different interaction with the columnmaterials, which lead to different elution profiles. Based on elutionprofile, it can be determined whether the elution conditions can beapplied to a continuous method (e.g., SSMB) to fractionate sugars. Anexemplary elution profile is provided in FIG. 7.

A pulse test chromatogram demonstrates that xylose eluting last, and allother monomeric sugars and oligomers elute first. The separationdemonstrated is sufficient to support scaling up of this chromatographicfractionation to a simulated moving bed (SMB) mode or sequentialsimulated moving bed (SSMB) continuous system.

Example 7 Hydrolysis of Hemi Cellulose-Depleted LignocellulosicMaterials in a Counter-Current Continuous Hydrolysis System

Eucalyptus wood chips were subject to hemicellulose sugar extraction asdescribed in Examples 1 and 2. The hemicellulose-depleted lignocelluloseremainder material was used in this Example.

The stirred tank hydrolysis reactor system is described in FIG. 8A. Anautomatically controlled and monitored 4-tank system was used. Milledhemicellulose-depleted lignocellulose material (e.g., particles of anaverage size ˜1400 microns) is suspended in an aqueous solutioncontaining approximately 33% HCl and 8% sugar. The suspension has about5% solids. The suspension is fed to tank 1 at a rate of 5 gph.Simultaneously, a 42% HCl solution is fed at approximately 2 gph to tank4. The solution at each tank is circulated by a pump at a rate of 50 gpmto adequately keep the solution in the tank mixed and allow good crosssectional flow through the a separation membrane which is part of theflow loop. The permeate from the membrane of tank 1 is diverted to thehydrolysate collection tank for de-acidification and refining. Theretentate of tank 1 is returned to the tank for further hydrolysis, anda portion of the flow is transferred to tank 2 in order to maintain aconstant level in tank 1. All the tanks in series are set at the sameparameters of permeate flow and level control. Typical acid and sugarconcentrations are depicted in FIG. 8B. The temperature of each tank istypically held at 60 F, 55 F, 50 F, 50 F for tanks 1 through 4respectively. The retentate for tank 4 is transferred to the ligninwashing process based on the same level control.

The results of 30 days continuous hydrolysis of hemicellulose-depletedeucalyptus are depicted in FIG. 8B. The black lines show target valuefor % HCl at reactor 1 though 4 and the hydrolysate collection tank thattransfers it to wash (de-acidify), and the % sugars (corresponding tototal dissolved sugars in the solution) values for tanks 1 through 4 andthe collection tank, while the gray lines show the average valuecollected over 30 days for the same points. The counter-current natureof the system is visualized: the acid entered the system at reactor 4and progressed towards 3, 2, and 1. The sugars were continuouslydissolved so that sugar level increased in the same direction. The solidmass entered at reactor 1, progressing and decreasing through 2, 3 and4.

When an additional reactor (“reactor 0”) is used before thehemicellulose-depleted lignocellulose material entered reactor 1,hydrolysis of highly oligomeric soluble sugars can be accelerated. Inreactor 0, the hemicellulose-depleted lignocellulose material iscontacted with acid for 15-20 minutes at elevated temperature (35-45°C.). Once these oligomers continue to hydrolyze to smaller unitsviscosity drops down sharply. It was observed that, when reactor 0 wasused, the average % sugar at all stages increased. Typically thishydrolysis system yields greater than 97% of the cellulosic and remainsof hemicellulosic polymers to dissolve in the hydrolysate as oligomericand monomeric sugars. The solid leaving hydrolysis comprise essentiallylignin and less than 5%, usually less than 3% bound cellulose.

Example 8 Hexanol Extraction, Back Extraction, and Acid Recovery

The hydrolysate produced in the hydrolysis system flows to theextraction system to remove the acid from the aqueous phase and recoverit for further use. HCl is extracted in a counter-current extractionsystem including 2 extraction columns (extraction A and extraction B)utilizing hexanol as the extractant. All extraction and back extractionprocesses are performed at 50° C. FIG. 9A shows data collected over 30days of the level of HCl in the hydrolysate moving into the extractionsystem (upper line), the level is ˜30%; the level of acid afterextraction A moving into extraction B (dark squares), the level is ˜8%;the level of residual acid after extraction B (gray triangles) the levelis less than 5%, typically 2-3%. Water is co-extracted with the acid,consequently the aqueous phase becomes more concentrated, typical sugarlevel is 16-20%.

The aqueous phase is then directed to further treatment. The loadedorganic phase is first washed to recover sugars from the solvent and thesugars, then to back extraction to recover the acid for recycling. Thesolvent wash is conducted in a column similar to that used forextraction with HCl solution at 20-25% weight/weight. FIG. 9B depictsthe level of sugars in the solvent phase after extraction B entering thewash column (upper line) which is typically 0.2-0.4%, and the level ofsugars in the washed solvent phase (lower line), typically less than0.05%. Next, the solvent is back extracted in another counter currentextraction column by running against an aqueous phase containing lessthan 1% HCl. FIG. 9C shows data accumulated over 30 days run, where thelevel of HCl in the solvent entering back extraction is ˜8% (graytriangles), the level of HCl in the solvent after back extraction isless than 0.5% (bottom line), and the level of acid in the aqueous phaseleaving back extraction is ˜18.5%.

Example 9 Secondary Hydrolysis

The sugar solution coming out of extraction typically contains about2.5% HCl and 16-20% sugars, however typically only 60-70% of thesesugars are present as monomers. The sugar solution was diluted to haveless than 13% sugars and about 0.6% residual acid. The solution washeated in a stirred tank to 120° C. for about 45 minutes, the resultingcomposition comprises more than 90% monomers. It was than cooled tolower than 60° C. to prevent re-condensation of the monomers. Datacollected over 30 days is depicted in FIG. 10, showing the % monomericsugars (out of total sugars) before secondary hydrolysis (lower line)and after secondary hydrolysis.

Example 10 Amine Purification

The sugar solution after secondary hydrolysis was sent to the amineextraction process where the solution was contacted with an extractantcontaining tri-laurylamine and hexanol in a 45:55 ratio. The extractantto sugar feed ratio (0/A) of 1.8:1 wt:wt was used and the extraction iscontrolled at a temperature of 50-60° C. Extraction is carried out in amixer-settler. Residual acid was extracted into the organic phase,residual organic acids, furfurals and phenolic molecules (ligninrelated) were also extracted into this phase. FIG. 11A shows pH measuredin the aqueous phase going into amine purification, FIG. 11B shows thecalculated efficiency of acid extraction into the amine/hexanol phase asmeasured by titration of the organic phase. The loaded extractant issent to another mixer-settler where the solvent was back-extracted witha base (typically Mg(OH)₂ or NaOH). Finally, the solvent was sent to athird mixer-settler where the solvent was washed with water. Once washedthe solvent was recycled back to the first extraction stage.

Example 11 Hexanol Purification from the Main Solvent Extraction Step

The solvent from the main extraction process extracts along with acidand water much of the impurities present in the hydrolysate. Inaddition, organic acids react under the acidic conditions to form esterswith the alcoholic solvent (e.g., hexyl acetate, hexyl formate). Afraction (e.g., ˜10%) of the back extracted solvent from the previousextraction process was separated and treated with lime (e.g., with anaqueous phase containing 10% lime slurry). By doing so, these impuritieswere removed. The lime addition was set at approximately a 1.5 weight %of the hexanol charged to the reactor. The 2 phase system was agitatedat 80° C. for 3 hours. The solution was then cooled to <50° C., thephases were separated in a mixer settler and the solvent phase waswashed with water before returning to the extraction solvent feed.

The level of impurities in the treated hexanol, including furfurals,hexyl formate, hexyl acetate, hexyl chloride and hydroxymethylfurfural,was detected by gas chromatography. Data collected over 30 daysoperation is depicted in FIG. 12. The only impurity that was building upwas hexyl acetate. The kinetics of hydrolysis of hexyl acetate is theslowest of these impurities, which can be addressed by increasingtreatment conditions or fraction.

Example 12 Acid Recovery: Production of 42% Acid in a HCl Absorber

HCl gas recycled from the process by evaporation flew through acommercial falling film absorber (SGL). Two absorbers were used toensure a complete absorption of HCL gas. The absorbers were kept at5-10° C. (e.g., using a chiller). HCl gas was absorbed by a HCl solutionin the absorber to increase HCl concentration to high concentration(e.g., greater than 41%). Data collected during a 30-day operationperiod is shown in FIG. 13, which shows that the target concentration isgenerally achieved.

Example 13 Lignin Washing

A exemplary lignin washing system is shown in FIG. 14A. The lignin fromthe hydrolysis system entered the lignin wash system where it was washedin a counter-current system with a 5-20% HCl solution. A system of 7wash stages was used. The concentration of acid and sugars at each stage(average result over 30 days of data collection) is shown in FIG. 14B.In stage 1 the lignin suspension had about 4% sugars and about 34% HCl.The concentration of sugars and acid decreased over the 7 stages. Thesuspension leaving stage 7 typically comprises less than 2.0% sugars andjust over 27% HCl.

Example 14 Chemical Structure Characterization of High Purity LigninObtained from Limited-Solubility Solvent Purification

Lignin solid were washed according to Example 13. The washed lignin washeated in Isopar K to 100° C. to de-acidify the lignin. The de-acidifiedlignin was then separated from the liquid phase. The solid de-acidifiedlignin (˜20 Lb) was heated with a NaOH solution (28 lb NaOH and 197 lbof water) in an agitate reactor to 360° F. for 6 hours. The dissolvedlignin solution was allowed to cool down. The Isopar K organic phase andaqueous phase were separated. The aqueous lignin solution was contactedwith methylethylketone (MEK) at a ratio of ˜1:2 volume/volume. The pH ofthe aqueous solution is adjusted to 3.3-3.5 with HCl. The MEK phase wascollected and contacted with a strong acid cation exchanger. The refinedlignin solution was flash evaporated by dropping it into a hot waterbath (˜85° C.). The precipitated lignin was filtered and washed withwater on a filter press.

Element analysis of high purity lignin and a commercial lignin isprovided in the table below:

High purity Pine High purity Element Sigma Kraft lignin ligninEucalyptus lignin % C 47.96 56.17 65.9 % H 4.93 5.16 5.32 % N 0.1 ≦0.05≦0.05 % S 1.56 ≦1 ≦1 % O 25.57 23.06 28.1 Total 80.12 84.39 99.32 Total% Cl — 0.02 0.04 Formula C₉H_(11.02)O_(3.6) C₉H_(9.85)O_(2.77)C₉H_(8.65)O_(2.88)

Inductively coupled plasma (ICP) analysis of high purity pine lignin isprovided below:

Element Concentration (ppm) Calcium 2 Magnesium <1 Potassium <1 Silicon93 Sodium 101 Iron 104 Copper 2 Aluminum 23

Thermal properties of pine lignin are provided in the table below.

Moisture  2.9 (Wt/%)  5% degradation  251 (° C.) 10% degradation  306 (°C.) Char 44.4 (Wt/%)

The NMR results indicated that the high purity lignin has low aliphatichydroxyl group and high phenolic hydroxyl group, as shown in the tablesbelow and FIG. 15. The values for natural lignin are values reported inliterature.

Hydroxyl groups content in high purity lignin and natural ligninsAliphatic OH Carboxylic OH (mmole/g Phenolic OH (mmole/ Species lignin)(mmole/g lignin) g lignin) High purity Pine 0.31 2.78 0.49 Lignin (A)Pine high purity 0.35 2.92 0.91 Lignin (B) Eucalyptus high 0.31 3.240.46 purity Lignin Loblolly pine 4.16 0.77 0.02 Eucalyptus globulus 7.381.14 0.37 Black spruce 4.27 1.13 0.21 Wheat straw 3.49 1.46 0.12Miscanthus 4.00 1.53 0.13 Switchgrass 3.88 1.00 0.29 P. tremuloides 5.720.74 0.06 Pine Organosolv 4.43 3.48 — Poplar Organosolv 3.85 3.48 —Kraft lignin 5.09 — — EOL Loblolly pine 7.30 2.40 0.30 Miscanthus EOL1.26 3.93 0.28

¹³C NMR characterization of lignin Virdia Resid- {circumflex over( )}Native Virdia Euca- ual Euca- *Native Pine lyptus Kraft lyptus PineHP HP #Pine Soft- grandis Lignin Lignin Lignin EOL wood lignin Degree of0.4 0.9 0.9 1.1 1 0.2 condensation Methoxyl content 1 0.7 0.8 0.9 0.81.6 (#/aryl group) Aliphatic linkages 0.6 0.1 0.2 0.3 0.3 0.6 (β-O-4′)(#/aryl group) Aromatic C—O 2.0 1.8 1.9 2.1 2.1 2.0 (#/aryl group)Aromatic C—C 1.5 2.2 2.3 2.1 1.9 1.9 (#/aryl group) Aromatic C—H 2.6 2.11.7 2 2.0 2.1 (#/aryl group) syringyl/guaiacyl — — 0.5 — — 1.7 *“Effectsof two-stage dilute acid pretreatment on the structure and compositionof lignin and cellulose in loblolly pine”. Ragauskas A J, Bioenerg. Res2008; 1 (3-4): 205-214. #“Lignin structural modifications resulting fromethanol organosolv treatment of loblolly pine”. Ragauskas A J, EnergFuel 2010; 24 (1): 683-689. {circumflex over ( )}“Quantitativecharacterization of a hardwood milled wood lignin by nuclear magneticresonance spectroscopy”. Kadla J F. J Agr Food. Chem. 2005; 53 (25):9639-9649.

Example 15 Direct Lignin Extraction

After hemicellulose sugars were extracted from eucalyptus chips, theremainder was mainly cellulose and lignin. The remainder was delignifiedusing an aqueous organic solution containing acetic acid according tothe process described below.

Eucalyptus wood chips (20.0 g) were mixed with a solution of 50/50 v/vof methylethylketone (MEK) and water that contains 1.2% acetic acid w/wof solution at a ratio of 1:10 (100 mL water, 100 mL MEK, and 2.2 gacetic acid). The mixture was treated at 175° C. for 4 hours in anagitated reactor. Then the system was allowed to cool to 30° C. beforethe reactor is opened. The slurry was decanted and the solid iscollected for further analysis.

After the reaction, there was 127 g free liquid, of which 47.2 g organicand 79.8 g aqueous. The organic phase contained 1.1 g acetic acid, 10.4g water, and 5.5 g dissolved solids (0.1 g sugars and 5.4 g others,which is mainly lignin). The aqueous phase contained 1.4 g acetic acid,2.1 g dissolved solids (1.5 g sugars and 0.6 g other).

After decanting of the liquid, black slurry and white precipitate wereat the bottom of the bottle. This material was vacuum-filtered andwashed thoroughly with 50/50 v/v MEK/water (119.3 g MEK 148.4 g water)at room temperature until the color of the liquid became very paleyellow. Three phases were collected; organic 19.7 g, aqueous 215 g, andwhite solid 7 g dry. The organic phase contained 0.08 g acetic acid and0.37 g dissolved solids. The aqueous phase contained 0.56 g acetic acidand 0.6 g dissolved solids.

All organic phases were consolidated. The pH of the solution is adjustedto pH 3.8. The solution was then allowed to separate into an aqueousphase (containing salts) and an organic phase (containing lignin). Thelignin-containing organic phase was recovered and purified using astrong acid cation column. The organic solution was then added drop-wiseinto an 80° C. water bath to precipitate the lignin.

¹³C Solids State NMR analysis of the white precipitate indicates that itcomprises mostly cellulose (pulp). The amount of lignin is notdetectable. The reaction is successful in delignifying the eucalyptuswood chips.

Example 16 Analysis of Hydrolyzed Cellulose Sugars from Pine Wood

Pine wood chips were subject to hemicellulose sugar extraction asdescribed in Examples 1 and 2. The cellulose hydrolysis was carried outusing a simulated moving bed hydrolysis system as described inPCT/US2011/057552 (incorporated herein by reference for all purposes).The cellulose sugar purification was conducted as described in Examples8 and 9. A strong base anion exchanger was used instead of amineextraction for sugar purification similar to example 10 (all is the sameexcept that the amine is in a solid phase, which is the SBA resin). Thecompositions of the cellulose sugars were described in the table below.

Analysis of hydrolyzed cellulose sugars from pine wood is providedbelow:

PARAMETER RESULT UNITS APPEARANCE Clear colorless viscous liquid pH 3.85Saccharides DS (HPLC) 73.5 % wt/wt % Total monosaccharides 96.7 DS/DSComposition (HPAE-PAD) XYLOSE 6.09 (4.59) DS/DS (w/w) ARABINOSE 1.13(0.86) DS/DS (w/w) MANNOSE 16.89 (12.73) DS/DS (w/w) GLUCOSE 56.61(42.66) DS/DS (w/w) GALACTOSE 3.16 (2.39) DS/DS (w/w) FRUCTOSE 14.31(10.79) DS/DS (w/w) Impurities Furfurals (UV) <0.001 % wt/wt Phenols(UV) 0.02 % wt/wt Metals & inorganics (ICP) Ca <2 ppm/DS Cu <2 ppm/DS Fe<2 ppm/DS K <2 ppm/DS Mg <2 ppm/DS Mn <2 ppm/DS Na 30 ppm/DS S 2.7ppm/DS P 9.5 ppm/DS

Example 17 Analysis of Hemicellulose Sugars from Pine Wood

Pine wood chips were subject to hemicellulose sugar extraction asdescribed in Examples 1 and 2. The hemicellulose sugar was purified asdescribed in Examples 3 and 5 except that a strong base anion exchangercontaining solid phase amine was used. The resulting sugar solution wasconcentrated. The compositions of the hemicellulose sugars weredescribed in the table below.

Analysis of hemicellulose sugars from pine wood is provided below:

PARAMETER RESULT UNITS APPEARANCE Clear, slightly yellow viscous liquidOdor Pass pH 3.10 Saccharides DS (HPLC) 70.0 % wt/wt % Totalmonosaccharides 74.4 DS/DS Composition (HPAE-PAD) XYLOSE 16.14 (11.30)DS/DS (w/w) ARABINOSE 6.89 (4.82) DS/DS (w/w) MANNOSE 24.53 (17.15)DS/DS (w/w) GLUCOSE 9.23 (6.46) DS/DS (w/w) GALACTOSE 10.65 (4.26) DS/DS (w/w) FRUCTOSE 10.82 (7.57)  DS/DS (w/w) Impurities Furfurals (UV)0.001 % wt/wt Phenols (UV) 56.1 ppm/DS Metals & inorganics (ICP) Ca 1.1ppm/DS Cu ND** ppm/DS Fe ND ppm/DS K ND ppm/DS Mg 0.1 ppm/DS Mn NDppm/DS Na 6.8 ppm/DS S 11.4 ppm/DS P 7.4 ppm/DS

Example 18 Analysis of Hemicellulose Sugars from Eucalyptus

Eucalyptus wood chips were subject to hemicellulose sugar extraction asdescribed in Examples 1 and 2. The hemicellulose sugar was purified asdescribed in Examples 3 and 5. The compositions of the hemicellulosesugars were described in the table below.

Analysis of hemicellulose sugars from Eucalyptus is provided below:

PARAMETER RESULT UNITS APPEARANCE Colorless pH 3.13 Saccharides DS(HPLC) 72.37 % wt/wt % Total monosaccharides 91.71 DS/DS (w/w)Composition (HPAE-PAD) XYLOSE 67.23 (48.65) DS/DS (w/w) ARABINOSE 3.09(2.24) DS/DS (w/w) MANNOSE 5.83 (4.22) DS/DS (w/w) GLUCOSE 4.64 (3.36)DS/DS (w/w) GALACTOSE 8.22 (5.95) DS/DS (w/w) FRUCTOSE 3.40 (2.46) DS/DS(w/w) Impurities Furfurals (UV) 0.0005 % wt/wt Phenols (FC) 0.047 %wt/wt Metals & inorganics (ICP) Ca <2 ppm Cu <2 ppm Fe <2 ppm K <2 ppmMg <2 ppm Mn <2 ppm Na 22 ppm S 6.7 ppm P 4.2 ppm

Example 19 Analysis of Sugar Stream

Bagasse is subject to hemicellulose sugar extraction as described inExamples 1 and 2. The hemicellulose sugar is purified as described inExamples 3 and 5. The resulting sugar solution is concentrated andfractionated as described in Example 6, to obtain a xylose rich solutioncontaining more than 80% xylose, and a second stream containingoligomeric and monomeric sugars. The composition of the sugar mixture isgiven in the table below.

Carbohydrate % wt/DS (dissolved sugars) Oligomers 23.2% Monomerscomposition out of total dissolved sugars: Glucose and fructose¹ 27.6%Mannose 0.2% Galactose 2.9% Xylose 32.4% Arabinose 13.7%

Example 20 Hydrolysis of Cellulose by Cellulase

Cellulose pulp (eucalyptus pulp) was obtained as the remainder after thehemicellulose and lignin extraction. Cellulose pulp suspension having10-20% solids in 0.05M acetate buffer, pH 4.55, 5%/cellulose,cellulase:cellobiase 1:1 was prepared. The suspension was stirred at 55°C. Samples of the liquor were taken periodically for analysis of thedissolved sugars. The dissolving sugars were mostly glucose, but canalso include some residual hemicellulose sugars remaining in the pulp.The dissolved sugar contained 7.78% lignin and 94.22% holocellulose,(89.66% glucose). As % solids increased, overall yield decreased (solong as the enzyme loading is the same). However the yield was highercompared to a reference sample hydrolyzed under the same conditionsusing Sigmacell (Sigma # S5504 from cotton linters, type 50, 50 um), asseen in FIG. 42B. the cellulose pulp is well saccharified by thecellulase mix enzyme (although it still contains some residual lignin)the reaction rate of E-HDLM is higher than the reference material

Example 21 Improvement to SSMB Sequence for Higher Product Recovery

Separation of xylose from the hemicellulose sugar mix was conducted on apurposely build, ProSep SSMB Operation model, 12 column carousel designSSMB system (hereinafter ProSep SSMB Operation 2.0). The improvedsequence contained 6 stages, each of which has two columns. The columnswere packed with Finex AS 510 GC, Type I, SBA, gel form, Styrenedivinylbenzene copolymer, functional group trimethylamine, specificgravity 1.1-1.4 g/cm³, mean bead size 280 millimicrons. The gel was inthe sulfate form. It was pre-conditioned with 1.5 bed volume (BV) of 60mM OH⁻, adjusting the resin to 8-12% OH and leaving the remainder in thesulfate form. The table below compares common pulse sequence of theProSep SSMB Operation 1.0 (original model) with the improved sequence ofProSep SSMB Operation 2.0.

ProSep SSMB ProSep SSMB Step Operation 1.0 Operation 2.0 Step 1 (Desorbto Extract; Feed to Raffinate) Step 1 Time 233 seconds 331.5 secondsExtract Flow 77.0 ml/min 80.4 ml/min Raffinate Flow 63.5 ml/min 92.0ml/min Step 2 (Desorb to Raffinate; Desorb to Extract) Step 2 Time 345seconds 376.1 seconds Raffinate Flow 63.5 ml/min 92.0 ml/min ExtractFlow — 33.5 ml/min Step 3 (recycle) Step 3 Time 1028 seconds 864 secondsRecycle Flow 63.5 ml/min 60 ml/min Results Purity   79% 84.9% Recovery81.7%   84% Desorb to Feed Ratio 2.7 2.37 Total Step Time 26.76 minutes26.2 minutes

Xylose was separated according to the improved sequence of ProSep SSMBOperation 2.0. A feed solution containing about 30% weight/weight sugarswas provided. The feed solution contained about 65% weight/weight xyloseout of total sugars. The product stream containing about 16.4% sugarswas extracted. The product stream contained more than 80% weight/weight(e.g., in some cases, more 82%, 84%, 85% weight/weight) xylose out oftotal sugars. The recovery was greater than 80% weight/weight. Theraffinate containing about 5% weight/weight total sugars was obtained.The raffinate contained only about 16.5% weight/weight out of totalsugars.

1-329. (canceled)
 330. A xylose-enriched stream hemicellulose sugarmixture comprising two or more, of the following characteristics: (i)oligosaccharides in a ratio to total dissolved sugars <0.10weight/weight; (ii) xylose in a ratio to total dissolved sugars >0.50weight/weight; (iii) arabinose in a ratio to total dissolved sugars<0.10 weight/weight; (iv) galactose in a ratio to total dissolved sugars<0.05 weight/weight; (v) the sum of glucose and fructose in a ratio tototal dissolved sugars <0.10 weight/weight; (vi) mannose in a ratio tototal dissolved sugars <0.02 weight/weight; (vii) fructose in a ratio tototal dissolved sugars <0.05 weight/weight; (viii) furfurals in anamount up to 0.01% weight/weight; (ix) phenols in an amount up to 500ppm; and (x) hexanol in an amount up to 0.1% weight/weight.
 331. Themixture of claim 330, wherein the oligosaccharides to total dissolvedsugars ratio is <0.07.
 332. The mixture of claim 330, wherein theoligosaccharides to total dissolved sugars ratio is <0.05.
 333. Themixture of claim 330, wherein the xylose to total dissolved sugars ratiois >0.40 weight/weight.
 334. The mixture of claim 330, wherein thexylose to total dissolved sugars ratio is >0.70 weight/weight.
 335. Themixture of claim 330, wherein the xylose to total dissolved sugars ratiois >0.80 weight/weight.
 336. The mixture of claim 330, wherein the sumof glucose and fructose to total dissolved sugars ratio is <0.09. 337.The mixture of claim 330, wherein the sum of glucose and fructose tototal dissolved sugars ratio is <0.05.
 338. The mixture of claim 330,comprising furfurals in an amount up to 0.005% weight/weight.
 339. Themixture of claim 330, comprising furfurals in an amount up to 0.001%weight/weight.
 340. The mixture of claim 330, comprising phenols in anamount up to 60 ppm.
 341. The mixture of claim 330, comprising phenolsin an amount up to 0.05 ppm.
 342. The mixture of claim 330, comprising:(ii) xylose in a ratio to total dissolved sugars >0.50 weight/weight;(viii) furfurals in an amount up to 0.01% weight/weight; (ix) phenols inan amount up to 500 ppm; and (x) hexanol in an amount up to 0.1%weight/weight.
 343. A hemicellulose sugar mixture comprising two or moreof the following characteristics: (i) monosaccharides in a ratio tototal dissolved sugars >0.50 weight/weight; (ii) glucose in a ratio tototal monosaccharides <0.25 weight/weight; (iii) xylose in a ratio tototal monosaccharides >0.18 weight/weight; (iv) fructose in a ratio tototal monosaccharides <0.10 weight/weight; (v) fructose in a ratio tototal monosaccharides >0.01 weight/weight; (vi) furfurals in an amountup to 0.01% weight/weight; (vii) one or more phenols in an amount up to500 ppm; and (viii) hexanol in an amount up to 0.1% weight/weight. 344.The mixture of claim 343, wherein the monosaccharides to total dry solidratio is >0.70 weight/weight.
 345. The mixture of claim 343, wherein themonosaccharides to total dry solid ratio is >0.90 weight/weight. 346.The mixture of claim 343, wherein the glucose to total monosaccharidesratio is <0.15 weight/weight.
 347. The mixture of claim 343, wherein theglucose to total monosaccharides ratio is <0.13 weight/weight.
 348. Themixture of claim 343, wherein the glucose to total monosaccharides ratiois <0.06 weight/weight.
 349. The mixture of claim 343, wherein thexylose to total monosaccharides ratio is >0.20 weight/weight.
 350. Themixture of claim 343, wherein the xylose to total monosaccharides ratiois >0.50 weight/weight.
 351. The mixture of claim 343, wherein thexylose to total monosaccharides ratio is >0.70 weight/weight.
 352. Themixture of claim 343, wherein the fructose to total monosaccharidesratio is >0.02 weight/weight.
 353. The mixture of claim 343, wherein thefructose to total monosaccharides ratio is <0.08 weight/weight.
 354. Themixture of claim 343 comprising furfurals in an amount up to 0.005%weight/weight.
 355. The mixture of claim 343 comprising furfurals in anamount up to 0.001% weight/weight.
 356. The mixture of claim 343comprising phenols in an amount up to 400 ppm.
 357. The mixture of claim343 comprising phenols in an amount up to 300 ppm.
 358. The mixture ofclaim 343, further comprising: (ix) metals and inorganics selected fromthe group consisting of Ca, Cu, Fe, K, Mg, Mn, Na, S and P in an amountup to 100 ppm/DS; (x) lignocellulose degradation products selected fromthe group consisting of furfural, levulinic acid, and formic acid andfurfural in an amount up to 1.5% wt/wt; and (xi) acetic acid in anamount up to 0.035 wt/wt.
 359. A xylose-removed hemicellulose sugarmixture comprising two or more of the following characteristics: (i)oligosaccharides in a ratio to total dissolved sugars >0.15weight/weight; (ii) the sum of glucose and fructose in a ratio to totaldissolved sugars >0.20 weight/weight; (iii) arabinose in a ratio tototal dissolved sugars >0.02 weight/weight; (iv) galactose in a ratio tototal dissolved sugars >0.02 weight/weight; (v) xylose in a ratio tototal dissolved sugars <0.30; (vi) mannose in a ratio to total dissolvedsugars >0.01; (vii) fructose in a ratio to total dissolved sugars <0.05;(viii) furfurals in an amount up to 0.01% weight/weight; (ix) phenols inan amount up to 500 ppm; and (x) hexanol in an amount up to 0.1%weight/weight.
 360. The mixture of claim 359, wherein theoligosaccharides to total dissolved sugars ratio is >0.20 weight/weight.361. The mixture of claim 359, wherein the oligosaccharides to totaldissolved sugars ratio is >0.23 weight/weight.
 362. The mixture of claim359, wherein the sum of glucose and fructose to total dissolved sugarsratio is >0.10 weight/weight.
 363. The mixture of claim 359 comprisingfurfurals in an amount up to 0.005% weight/weight.
 364. The mixture ofclaim 359 comprising phenols in an amount up to 60 ppm.
 365. The mixtureof claim 359, wherein the xylose to total dissolved sugars ratio is<0.30 weight/weight.
 366. The mixture of claim 359, wherein the xyloseto total dissolved sugars ratio is <0.10 weight/weight.